Feb. 8, 1872] 



NATURE 



279 



Naples, a laboratory with a larger aquarium for the public. 

 The income of the latter in a place like Torquay, where 

 there are so many residents and visitors at all times of 

 the year, would completely suffice to keep up the labora- 

 tory, and pay a modest sum to a naturalist, who would be 

 charged with the management of the station. Being 

 unable to attend personally the meeting at Edinburgh, 

 I could not give all the reasons which induced me to make 

 this proposition. All the more I shall avail myself of the 

 present opportunity to do so. 



The present state of zoology requires, as stated above, 

 new means of investigation. Systematism and simple 

 faunistic researches fall very far short of the prob'ems 

 now ripe for solution. Two great departments of biologi- 

 cal science go much ahead of all others, and these two 

 are embryology and the study of the life of animals in 

 relation to all those conditions which regard the struggle 

 for existence and the action of natural selection. 



If we speak first of the latter chapter, it is clear that 

 past times have done much more in promoting knowledge 

 about it than the present generation. It is rather out of 

 fashion to study the habits and conditions of life of an 

 animal. Systematism, the making of grnera and species, 

 have so much exceeded their legitimate grounds, th jt they 

 have almost completely suppressed that other branch of 

 natural historj-. We owe it to iVIr. Darwin that he com- 

 pletely upset this one-sidedness, in proving, by his admi- 

 rable treatises on the Domestication of Animals and Plants, 

 on Sexual Selection, on the Fertilisation of Orchidcffi by 

 the Interference of Insects, of whatfimdamentalimportance 

 these studies of the habits and conditions of animal life 

 can be. He added not only an enormous number of 

 hitherto unknown facts to the storehouse of science, but 

 he showed what immense importance these facts gained 

 by deriving from them the great principle of natural selec- 

 tion — a principle as grand as any in modern science. 

 Very few zoologists (in naming Mr. Wallace and Mr. 

 Bates, I do justice to these eminent men as two of those 

 who promoted these studies independently of Mr. Dar- 

 win) have followed Mr. Darwin's lines in these depart- 

 ments. Nevertheless this must happen : it constiiutes 

 one of the most urgent necessities of biological study in 

 our time, and it must not only be done for our domestic 

 animals, and those that live most closely around us, but 

 wherever animals are to be found, and soabave all in that 

 enormous field of animal life which occurs in the sea. 



Every one will agree with me that we know scarcely 

 any of the secrets of the life of the sea bottom. We have 

 short notices on the habits of some fishes ; but this is 

 altogether insignificant compared with the immense bulk of 

 things unknown to us in the same department. And of 

 echinoderms, cuttle fish, jelly fish, polyps, iS:c., (ic, our 

 knowledge simply amounts to nothing. 



Here an aquarium, under scientific guidance and super- 

 intendence, can work immense good and progress. And 

 such an aquarium will do double service ; first, it will 

 attract the public and yield money ; and then it will serve 

 immediately and directly the progress of science, by giving 

 the only possibility of knowing something about the habits 

 and the life of marine animals. 



But a zoological station with an aquarium will serve 

 equally as much for the progress of embryology. Who- 

 ever looks at the development of biological science must 



see that, during the last ten years, embryology has made 

 very important progress, not only in accumulating facts, 

 but in rendering them serviceable to the progress of ideas 

 and principles. 



An offspring of the theory of descent is the maxim that 

 the ontogenetical development is an abbreviated recapitu- 

 lation of the phylogenetical development. This maxim, 

 or law, if we choose to call it a law, gives enormous 

 importance to embryology. By the help and application 

 of it we may succeed in gettiag a deep insight into the 

 history of animal life long before the geological record. 

 The Cambrian and Silurian systems yield us already a 

 fauna of so high perfection, and so complete a series of 

 representatives of almost eveiy great class of animals, 

 that we could easily be led to believe in a waving up and 

 down of animal creation, not in a constant progress, so 

 comparatively small are the differences between the pre- 

 sent fauna of the earth, and those which the geological 

 record of all the strata makes known to us. Embryology, 

 on the contrary, starts at the very beginning of organic 

 life, tells us how out of simple organic matter cells became 

 formed, how these cells took different functions, thus 

 differentiating and organising the being that possessed 

 them. Embryology further tells us how out of one form, 

 one single form, whole classes came forth, and renders it 

 possible for us to trace the lines of origin of every member 

 of ihese classes, down to the common ancestor of all of 

 them. 



Systematists, looking out anxiously for the " natural 

 syste/n " of the animal kingdom, and turning to mere 

 anatomical differences, may be compared to Sisyphus 

 rolling his stone. They cannot succeed without taking to 

 embryology. Butembryological studies are annngthe most 

 difficult in the whole range of biological science. Not 

 onlv the interpretation of the facts, and the conclusions to 

 be drawn from obs;rvation, require an immense aimunt of 

 circum!^pection, caution, and critical ability ; but even the 

 simple statement of a f act, the mere act of observation, 

 is often exceedingly difficult. How many monogriphs on 

 the embryology of the chicken have been written since 

 Ca-;par Friedrich Wolff published his immortal book 

 against the doctrines of Haller. Pandsr, Baer, Remak, 

 His, and many others, have treated the same subject, 

 and still to-day there is uncertainty on the most funda- 

 mental questions. This is above all to be attributed to the 

 mechanical difficulties of observation. And these diffi- 

 culties do not exist only in the case of birds' eggs ; they 

 are the same for the eggs of almost all animals, especially 

 for those of marine animals. These require a constant 

 stream of salt water to keep them alive, a stream which 

 is only to be had by the help of an aquarium. It is prin- 

 cipally due to the absence of such aquariums that our 

 knowledge of the development of fishes is still so rudi- 

 mentary ; for, though the works of Baer, Rathke, Vogt, 

 Lereboullet, Kupffer, and others have taught us a good 

 deal, nevertheless the essential parts of fish-embryo- 

 logy are still wanting. And this is the more to be re- 

 gretted as it cannot be doubted that the eggs of fishes 

 are, in inany regards, preferable as objects for the investi- 

 gation of general embryo'.ogical facts to those of the 

 birds. Considering only the fact that all other vertebrata 

 have proceeded from fishes, most likely from shark-like 

 animals, it will be of the greatest importance to acquire 



