126 MR J. T. CUNNINGHAM ON THE 



The ovum of this species is stated by Ryder to possess four filamentous 

 processes connected with the vitelline membrane ("Development of Belone 

 longirostris" Bull. U.S. Fish Commission, vol. i.). The threads or filaments are 

 more completely described by Ryder in vol. ii. of the same bulletin, the 

 fish being there called Menidia, which is a synonym. The threads are in length 

 about eight times the diameter of the ovum, and when the latter is first 

 emitted the threads lie coiled spirally round it. There can be little doubt that 

 the four threads are merely the outer layer of the zona radiata in a specialised 

 form, and are homologous with the suspensory membrane in Osmerus. 



Fam. 3. Mugilhle. 



Div. XII. Acanth. Gastrosteiformes. 



Fam. 1. Gastrosteid^e. 



The ova of Gastrosteus are adhesive, and deposited in nests made with water 

 plants, and guarded by the male. Spinachia vulgaris makes nests of seaweeds, 

 Fucus, &c, on the sea-shore ; its ova are similar to those of Gastrosteus, but 

 larger. It has been shown by Prof. Karl Mobtus of Kiel, that the white fila- 

 ments, by which the nest of Spinachia is held together, are spun by the male 

 fish, and that they are formed from a substance resembling mucin which is pro- 

 duced in the kidneys (see Schr. Naturwiss. Vereins fur Schleswig Holstein, Bd. 

 vi., 1885; translated in Ann. and Mag. Nat. Hist., Aug. 1885: also E. E. 

 Prince, Ann. and Mag., Dec. 1885). The ova of Spinachia, according to 

 Prince, are "085 inch in diameter. A large mass of pale yellow oil globules 

 are aggregated at the yolk pole. At temperature 41° to 51° Fahr., in June the 

 ova hatched in twenty-five to forty days. No figures of the development are 

 given by Prince. 



Fam. 2. FiSTULARiiDiE. 



Div. XIII. Acanth. Centrisciformes. 

 Fam. 1. Centriscid^e. 



Div. XIV. ACA.NTH. GOBIESOCIFORMES. 



Fam. 1. Gobiesocid^e. 



Lepadogaster Decandolii. — Some observations on the development of this 

 species are described by W. Anderson Smith in Proc. Roy. Phy. Soc. Edin., 

 1886. The ova are adhesive, attached to stones or shells, and watched over 



