Miscellaneous, 227 



Rhynchosaurus and the probably Triassic African and Asiatic allies 

 of that genus, or to the Mesozoic Dinosauria, and that, whether 

 the age of the deposit in which it occurs be Triassic or Devonian, 

 Telerpeton is a striking example of a persistent type of animal or- 

 ganization. — Proc. GeoL Soc. Dec. 19, 1866. 



On the Incubation of the Eggs of the Small Spotted Dogfish (Scyl- 

 lium catulus). By M. Coste. 



At Concarneau, in a reservoir of 1500 metres surface and of 

 3 metres in depth, divided into six compartments, hollowed out in a 

 granite rock and defended by thick walls from the violence of the 

 waves, we have succeeded, by means of grated floodgates which may 

 be opened or closed at pleasure, in imitating the conditions of the 

 open sea, with its flux and reflux, so well that organic phenomena 

 hitherto most completely concealed in the depths of the ocean are 

 accomplished there under the eye of the observer. Not only do 

 most of the species live there in a state of familiar domesticity, ex- 

 hibiting all the peculiarities of their habits, but their reproduction is 

 effected, presenting a new field of observation in embryogeny. Of 

 this the following is a fresh example : — 



"At the beginning of April 1866," M. Guillou writes to me, "we 

 put into one of the compartments of the vivarium a pair of the Little 

 Spotted Dogfish (Squalus catulus, Linn.). The female laid eighteen 

 eggs in the course of the month. These eggs hatched at the begin- 

 ning of December ; the incubation therefore lasts about nine months. 

 The young are very lively." 



Thus a phenomenon which lasts nine months (and one of the most 

 delicate phenomena, since it implies the formation of a superior 

 organism) may be accomplished under these artificial conditions with 

 as much certainty as if it took place at the great depths where this 

 species usually deposits its eggs. This, in my opinion, is one of the 

 most decisive proofs of the perfection of the vast hydraulic apparatus 

 in which we carry on our experiments. Thanks to the perfection of 

 this apparatus, we shall henceforward study the development of 

 marine species, day by day and hour by hour, just as we investigate 

 that of the chicken in the egg. 



At one of the extremities of the vivarium there is a large building, 

 of which the ground-floor is provided with numerous aquaria for the 

 isolation of objects which it is desired to observe closely ; whilst its 

 first floor has been converted into rooms for dissections and micro- 

 scopic observations. Six French and foreign naturalists came 

 last summer to take their places in this laboratory, and devoted 

 themselves in perfect freedom to any investigations that they chose 

 to undertake. I offer the same hospitality to any who may be dis- 

 posed to profit by it. It is from this laboratory that we have derived 

 all the principles which served for the basis of the regulation of the 

 marine fisheries, and all the methods the application of which justly 

 claims the title of the "agriculture of the sea." — Comptes Rendus, 

 January 21, 1867, pp. 99-100. 



