quite a different form from what he had originally sketched out. But his chief interest lay in the Invertebrata. From April 29 to June 3 he lectured to working men at Jermyn Street upon the Crayfish; read a paper on the Classification and Distribution of Crayfishes at the Zoological Society on June 4, and lectured at the Zoological Gardens weekly from May 17 to June 21 on Crustaceous Animals. In all this work lay the foundations of his subsequent book on the Crayfish, which I find jotted down in the notes of this year to be written as an introduction to "Zoology," together with the "Dog" as an introduction to the "Mammalia", and "Man"--already dealt with in "Man's Place in Nature"--as an introduction to "Anthropology." This projected series is completed with a half-erased note of an introduction to "Psychology," which perhaps found some expression in parts of the "Hume," also written this year.

He notes down also, work on the Ascidians, and on the morphology of the Mollusca and Cephalopods brought back by the "Challenger," in connection with which he now began the monograph on the rare creature Spirula, a remarkable piece of work, being based upon the dissections of a single specimen, but destined never to be completed by his hand, though his drawings were actually engraved, and nothing remained but to put a few finishing touches and to write detailed descriptions of the plates.

Letters to W.K. Parker and Professor Haeckel touch on this part of his work; the former, indeed, offering a close parallel to a story, obviously of the same period, which the younger Parker tells in his reminiscences, to illustrate the way in which he would be utterly engrossed in a subject for the time being. Jeffery Parker, while demonstrator of biology, came to him with a question about the brain of the codfish at a time when he was deep in the investigation of some invertebrate group.] "Codfish?" [he replied,] "that's a vertebrate, isn't it? Ask me a fortnight hence, and I'll consider it."

4 Marlborough Place, September 25, 1878.

My dear Parker,

As far as I recollect Ammocoetes is a vertebrated animal--and I ignore it.

The paper you refer to was written by my best friend--a carefulish kind of man--and I am as sure that he saw what he says he saw, as if I had seen it myself.

But what the fact may mean and whether it is temporary or permanent--is thy servant a dog that he should worry himself about other things with backbones? Not if I know it.

Churchill has got over a whole batch of the American edition of the Vertebrata, so I have a respite. Mollusks are far more interesting--bugs sweeter--while the dinner crayfish hath no parallel for intense and absorbing interest in the three kingdoms of Nature.

What saith the Scripture? "Go to the ANT thou sluggard." In other words, study the Invertebrata.

Ever yours very faithfully,

T.H. Huxley.

[Sketch of a vast winged ant advancing on a midget, and saying, as it looks through a pair of eyeglasses, "Well, really, what an absurd creature!!"]

4 Marlborough Place, London, April 28, 1878.

My dear Haeckel,

Since the receipt of your letter three months ago, I have been making many inquiries about Medusae for you, but I could hear of none--and so I have delayed my reply, until I doubt not you have been blaspheming my apparent neglect.

My "Sammlung"!! [Collection.] My dear friend, my cabin on board H.M.S. "Rattlesnake" was 7 feet long, 6 feet wide, and 5 feet 6 inches high. When my bed and my clothes were in it, there was not much room for any collection, except the voluntary one made by some thousands of specimens of Blatta orientalis [The cockroach.], with whose presence I should have been very glad to dispense.

My Medusae were never published. I have heaps of notes and drawings and half-a-dozen engraved plates. But after the publication of the "Oceanic Hydrozoa" I was obliged to take to quite other occupations, and all that material is like the "full many a flower, born to blush unseen," of our poet.

If you would pay us a visit you should look through the whole mass, if you liked, and you might find something interesting.

At present, I am very busy about Crayfishes (Flusskrebse), working out the relations between their structure and their Geographical Distribution, which are very curious and interesting.

I have also nearly finished the anatomy of Spirula for the "Challenger." It is essentially a cuttlefish, and the shell is really internal. With only one specimen, it has been a long and troublesome job--but I shall establish all the essential points and give half-a-dozen plates of anatomy.

You will recollect my eldest little daughter? She is going to be married next Saturday. It is the first break in our family, and we are very sad to lose her--though well satisfied with her prospects. She is but just twenty and a charming girl, though you may put that down to fatherly partiality if you like.

The second daughter has taken to art, and will make a painter if she be wise enough not to marry for some years.

My eldest son who comes next is taller than I am. He has been at one of the Scotch Universities for the last six months; and one of these fine days, next month, you will see a fair-haired stripling asking for Herr Professor Haeckel.

I am going to send him to Jena for three months to pick up your noble vernacular; and in the meanwhile to continue his Greek and Mathematics, in which the young gentleman is fairly proficient. If you can recommend any Professor under whom he can carry on his studies, it will be a great kindness.

I will give him a letter to you, and while I beg you not to give yourself any trouble about him, I need not say I shall be very grateful for any notice you may take of him.

I am giving him as much independence of action as possible, in order that he may learn to take care of himself.

Now that is enough about my children. Yours must yet be young--and you have not yet got to the marriage and university stage--which I assure you is much more troublesome than the measles and chicken-pox period.

My wife unites with me in kindest remembrances and good wishes.

Ever yours very faithfully,

T.H. Huxley.

[An outbreak of diphtheria among his children made the spring of 1878 a time of overwhelming anxiety. How it told upon his strong and self-contained chief is related by T.J. Parker--"I never saw a man more crushed than he was during the dangerous illness of one of his daughters, and he told me that, having then to make an after-dinner speech, he broke down for the first time in his life, and for one painful moment forgot where he was and what he had to say." This was one of the few occasions of his absence from College during the seventies. "When, after two days, he looked in at the laboratory," writes Professor Howes, "his dejected countenance and tired expression betokened only too plainly the intense anxiety he had undergone."

The history of the outbreak was very instructive. Huxley took a leading part in organising an inquiry and in looking into the matter with the health officer.] "As soon as I can get all the facts together," [he writes on December 10,] "I am going to make a great turmoil about our outbreak of diphtheria--and see whether I cannot get our happy-go-lucky local government mended." [As usual, the epidemic was due to culpable negligence. In the construction of some drains, too small a pipe was laid down. The sewage could not escape, and flooded back in a low-lying part of Kilburn. Diphtheria soon broke out close by. While it was raging there, a St. John's Wood dairyman running short of milk, sent for more to an infected dairy in Kilburn. Every house which he supplied that day with Kilburn milk was attacked with diphtheria.

But with relief from this heavy strain, his spirits instantly revived, and he writes to Tyndall.]

4 Marlborough Place, May 20, 1878.

My dear Tyndall,

I wrote you a most downhearted letter this morning about Madge, and not without reason. But having been away four hours, I come home to find a wonderful and blessed change. The fever has abated and she is looking like herself. If she could only make herself heard, I should have some sauciness. I see it in her eyes.

If you will be so kind as to kiss everybody you meet on my account it will be a satisfaction to me. You may begin with Mrs. Tyndall!

Ever yours,

T.H. Huxley.

[Professor Marsh, with whom Huxley had stayed at Yale College in 1876, paid his promised visit to England immediately after this.]

4 Marlborough Place, N.W., June 24, 1878 (Evening).

My dear Marsh,

Welcome to England! I am delighted to hear of your arrival--but the news has only just reached me, as I have been away since Saturday with my wife and sick daughter who are at the seaside. A great deal has happened to us in the last six or seven weeks. My eldest daughter married, and then a week after an invasion of diphtheria, which struck down my eldest son, my youngest daughter, and my eldest remaining daughter altogether. Two of the cases were light, but my poor Madge suffered terribly, and for some ten days we were in sickening anxiety about her. She is slowly gaining strength now, and I hope there is no more cause for alarm--but my household is all to pieces--the Lares and