439 W yman's Observations on 
Arr. XXVI. — Observations on the Development of ANABLEPS 
Gronovu, ( Cuv. & Val.) By Jerrries Wyman, M. D. 
Read Sept. 90th, 1854. 
* 
Waie the general plan of the development of Fishes and 
Batrachian Reptiles conforms strictly to the an-allantoidian type, 
the external conditions under which the process of the form- 
ation of the embryo is carried on, vary to a very remarkable 
degree. In the larger majority of instances, eggs are scattered 
without care, or perhaps only a locality is selected which 
furnishes the most favorable circumstances, in relation to cur- 
rents of water, the kind of bottom, the exposure to light, &c. 
Once deposited, they are no longer attended to. 
In other cases, but these are comparatively few, the fishes 
construct something which serves to protect the eggs, and ina 
measure answers the purpose of a nest; in this the eggs are 
laid and undergo their evolution. The Lamprey builds a rude 
structure, consisting of a pile of stones brought from a dis- 
tance, in the mouth; both sexes codperating in the labor of 
building. The eggs are deposited between the stones as the 
structure is reared, and remain there in security until hatched. 
The Chub ( Catostomus tuberculatus) has a similar habit. Our 
But the most remarkable nests built by fishes, are those of the 
** Hassars ” ( Collicthys) of Demarara, and of the ^ Stickle- 
backs? (Gasterostei) of Europe. The * Round-headed ne 
sar” forms its nest of leaves, and the “ Flat-headed Hassar 
of grass. Of the two species of Stickleback described by Coste;t 
A * Owen. Leets. on Comp. Anat. Vol. TI. p. 304. | S i : 
= um structions Pratiques sur la Piscieulture, suivies de Memoires, ets 4 
ports aie méme sujet. Par M. Coste, Professeur au Collége de Les ! 
Paris, 1 
