368 



takes charge of the nest as soon as the eggs are laid, and 

 does not allow even the females to approach. He also con- 

 tinues to protect the young fish for some time after they are 

 hatched. The time of the incubation of the G. biaculeatus 

 is fifteen days. The common bream Pomotis vulgaris hol- 

 low out a place on the borders of the pond, and both sexes 

 keep watch over the nest till the young are hatched. The 

 Horned Pout Pimelodus atrarius does the same, but in this 

 species the female alone takes charge of the nest and re- 

 mains with the yonng for some time after they are hatched, 

 so that occasionally she is seen surrounded by several hun- 

 dreds of them. 



Mr. C. Cooke called the attention of the Society to the 

 fact of lately finding some of our Crustaceans, the genera 

 Gammarus, Asellus, Idotcea, and Branchipus, with their 

 eggs, and spoke of the importance of recording these and 

 kindred facts so as to be able to study their development, as 

 but little is known of the younger stages of that class and 

 consequently some confusion had occurred. He mentioned 

 that even by writers of the present day, some ef the embry- 

 >onic forms were mistaken and described for adult animals, 

 as for instance, in the Megalopid(B, the Marestia, Blonolepis, 

 Meg-alopa, &c., which are evidently the young of some of 

 the Cancroidea or Grapsoidea, and wished that persons no- 

 ticing anything of the kind, would cause a record to be made 

 of the fact. 



After the discussion of a few incidental topics by the Chair 

 and others, suggested by the previous remarks, the Institute 

 then adjourned. 



