NATURE 



437 



THE FOUNDATION OF ZOOLOGICAL 



ST A TIONS 



II. — The Aquarium at Naples 



WHEN I wrote the first article on the "The Founda- 

 tion of Zoological Stations,"* I desired to bring 

 before the general public the idea of extending the principle 

 of co-operation in Science in general, and in Biology in 

 particular. I now propose to give a sketch of the in- 

 ternal organisation of a zoological station as it presents 

 itself to my mind. It is natural that in doing this I give 

 more or less a picture of what I intend to produce at 

 the station which is at present being erected under my 

 superintendence at Naples. 



The building occupies an area of 7,000 square feet, and 

 is situated at a very short distance — looft. — from the sea. 

 It forms a rectangle looft. long and 70ft. broad, with 

 a height of 40ft. The building is divided into two parts, 

 the lower part being occupied by the tanks of the great 

 aquarium, which is to be open to the public ; the upper 

 part containing twenty-four rooms of different sizes for 

 laboratories, a library, and collections, and for lodging the 

 three or four zoologists who will be constantly occupied in 

 managing the station. 



I will not speak here of the manner in which the 

 technical parts of the aquarium arc to be arranged, as 

 this would scarcely interest my readers. What I should 

 like to specialise a little relates more to the facilities for 

 scientific study which the station will afford. 



Let me speak first of the lower part of the building, 

 the -great pubHc aquarium. It will contain fifty-three 

 tanks of different sizes, one of them 32ft. long, loft. 

 broad, and 3ft. to 6ft. deep ; twenty-six 6ft. 6in. long, 

 and equally broad ; and twenty-six others 3ft. long and 

 3ft. to 6ft. broad. These tanks will contain marine animals 

 of all kinds, either isolated or more or less mixed, accord- 

 ing to the investigations that are to be made. 



I imagine now that in one of these tanks a number of 

 MedusK and Salpa; are together, and the problem is 

 to know how they will behave in so close a union. This 

 can be solved only in such a tank, and it will be a very 

 easy study, as the naturalist has only to occupy a mov- 

 able chair, which is placed before the tank, and which 

 hides him and the tank by special precautions completely 

 from the general public. At a certain moment you can 

 put into the tank some rapacious fishes, or some of the 

 swift and warlike Crustaceans of the Palremon tribe, 

 and wait for the movements and actions of the Me- 

 dusa; as well as the Salpse. You may repeat these obser- 

 vations, and add other different species ; and if you have 

 patience enough, you cannot fail to discover facts about 

 the general habits of the animals in question, and the 

 functions of their organs, which were unknown before, 

 and which may yield, perhaps, valuable arguments to 

 establish a theory on the manner in which they origi- 

 nated from other animals. As it is, we hardly know 

 anything about the life of Medusa; or SalpE, and our 

 ignorance of the habits of other marine animals is 

 equally great. 



* Natl'Re, vol. V. p. 277. 

 VOL. V. 



Let us take another example. I was present when halt 

 a dozen stone crabs {Lithodes Maya) were brought from 

 Norway to the Hamburg Aquarium. Mr. Lloyd, at that 

 time the Director of the Aquarium, distributed them in 

 several tanks. It happened that one of them found itself 

 in company with a number of Crerilabrus Jiorwcgicus. 

 a swift and clever little fiih. These at once began to 

 attack their new companion. With considerable skill 

 they tried to hurt the eyes of the crab, which on their 

 long stalks presented, of course, the most vulnerable part 

 of the clumsy and spinous animal. After half an hour's 

 continued attacks the fishes actually succeeded in tearing 

 out one of the eyes. This fact made me investigate at 

 once the mode of protection with which Nature had fur- 

 nished the eyes of Crustacea, and I collected a considerable 

 number of observations, which, if completed and worked 

 out, would possibly form a very interesting chapter in our 

 knowledge of the progress of Natural Selection. 



I shall adduce a third instance for the necessity of 

 facilitating observations of this kind. In his excellent 

 refutation of some of Mr. Mivart's objections to 

 the theory of Natural Selection, Mr. Darwin relates 

 ("Origin of Species," 6th Edition, p. 1S6) some observa- 

 tions made by Malm on the way in which the eyes of 

 the Pleuronectes get both on one side of fish. The fol- 

 lowing are his words :— 



" The Plcuronectida:, whilst very young and still sym- 

 metrical, with their eyes standing on opposite sides of the 

 head, cannot long retain a vertical position, owing to the 

 excessive depth of their bodies, the small size of their 

 lateral fins, and to their being destitute of a swim-bladder. 

 Hence, soon growing tired, they fall to the bottom on one 

 side. Whilst thus at rest they often twist, as Malm 

 observed, the lower eye upwards, to see above them ; and 

 they do this so vigorously that the eye is pressed hard 

 against the upper part of the orbit. The forehead between 

 the eyes consequently becomes, as could be plainly seen, 

 temporarily contracted in breadth. On one occasion 

 Malm saw a young fish raise and depress the lower eye 

 through an angular distance of about seventy degrees. 

 We should remember that the skull at this early age is 

 cartilaginous and flexible, so that it readily yields to 

 muscular action. Besides, Malm states that the newly- 

 hatched young of perches, salmon, and several other sym- 

 metrical fishes, have the habit of occasionally resting on 

 one side at the bottom ; and he has observed that they 

 often then strain their lower eyes so as to look upwards ; 

 and their skulls are thus rendered rather crooked. These 

 fishes, however, are soon able to hold themselves in a 

 vertical position, and no permanent effect is thus produced. 

 With the Pleuronectida;, on the other hand, the older they 

 grow the more habitually they rest on one side, owing to 

 the increasing flatness of their bodies, and a permanent 

 efiect is thus produced on the form of the head and on the 

 position of the eyes." 



I think observations of this kind ought to speak so 

 much in favour of a great observatory for marine animals, 

 that it would be superfluous to add any more instances 

 for its necessity. I hope the Naples Institution will 

 rapidly produce a great number of similar observations, 

 and thus render one of the most important services to 

 the still utterly neglected knowledge of the animal life 

 of the ocean. 



Let us now ascend the staircase from the lower part of 

 the future Zoological Station to the upper floor. We pass 

 through a series of rooms on the north side, the first of 



