PIPE-FISHES. 681 



soiitliwards to the Cape of Good Hope ; it attains a length of 

 18 inches. Another very common species, frequently met at 

 sea, and spread over nearly aU the tropical and sub-tropical 

 seas, is S. pclagicus, agreeably marked with alternate brown 

 and silvery cross-bars. 



DORYICHTHYS. — Body with the ridges well developed. Pec- 

 toral and caudal fins present. Dorsal fin long or of moderate 

 length, opposite to the vent. IJumeral bones firmly united. 

 Males Avith the lower ridges of the abdomen dilated, the dilated 

 parts forming a broad groove for the reception of the ova. 



In these Pipe-fishes the ova are not received in a com- 

 pletely closed pouch, but glued on to the surface of the 

 abdomen. Twenty species from trojDical seas, 



Nerophis. — Body smooth, rounded, with scarcely any of the 

 ridges distinct. Pectoral fin none, caudal absent or rudimentary, 

 the tail tapering into a point. Dorsal fin of moderate length, 

 opposite to the vent. The ova are attached to the soft integu- 

 ment of the abdomen of the male, and are not covered by lateral 

 folds of the skin. 



Seven species from the European seas and the Atlantic. 

 N. cequoreus (Ocean Pipe-fish), H. 02')liidion (Straight-nosed 

 Pipe-fish), and N. lumhriciformis (Little Pipe-fish), are common 

 on the British coasts. 



Protocampus. — The whole dermal skeleton is covered with 

 skin. A broad cutaneous fold runs along the back in front and 

 behind the dorsal ; a similar fold along the abdomen. Pectoral 

 fin none ; caudal very small. 



The single species of this remarkable genus, P. hymeno- 

 lomus, occurs in the Falkland Islands. It may be regarded 

 as an embryonal form of Nerophis, the median skin-folds being 

 evidently remains of the fringe which surrounds the body of 

 the embryo. 



The other genera belonging to tliis group are, Ichtlmjo- 

 campus, Nannocampus, Urocampus, Lcptoichtliys, Coelonotus, 

 and Stigmatophora. 



