1 86 BACKBONED ANIMALS. 



to time, and either eggs or newly-hatched young may be found in the 

 cavity of the gills or the space inclosed by the branchiostegal mem- 

 brane. The unhatched eggs, according to Agassiz, are always found 

 in the same position in the curious nursery namely, in the upper part 

 of the branchial arches, protected or held together by a special lobe or 

 valve formed of the upper pharyngeals. Here they are held until the 

 young are able to care for themselves. 



Sculpins (Cottidoi). These are marine fishes of fan- 

 tastic shape, each individual often varying in color. The 

 head and opercular bones are armed with sharp spines, 

 and the fishes resemble the mossy rocks amid which they 

 lie. The sea-raven, or yellow sculpin, is an allied form, 

 attaining a length of two feet, and is remarkable for its 

 grotesque coloring. The males of some species erect nests 

 for their young. Allied are the sea-robins (Triglidce). 

 The flying-robin (Dactylopterus] has enormous pectoral 

 fins by which it soars over the water like the flying-fish. 

 Sailors have been knocked over by them, and they are 

 frequently blown aboard vessels. 



Gobies (Gobiidce). The gobies are small fishes, in 

 which the thoracic ventrals are united, forming a hollow 

 disk. They have no air-bladders, and are remarkable for 

 their habit of leaving the water. The scaleless and black 

 gobies and several other species are found on the western 

 coast of North America. 



NOTE. In the Periophthalmus (frontispiece), common at the Feejee 

 Islands, Ceylon, and other localities, the pectoral fins are greatly devel- 

 oped, the head blunt, and the eyes staring and prominent. They leave 

 the water and hop along the shore so fast that it is difficult to catch 

 them, resembling frogs more than fishes. They feed out of water, pre- 

 ferring a shell-less mollusk, the Onckidium (Fig. 72), and insects. The 

 Boleophthalmus has similar habits. The Blennius pholis also leaves 

 the water at times. The black goby is said to build a nest for its eggs. 



Lump-Fish (Cyclopterida*)* The lump-fishes range 

 from the polar regions to Cape Hatteras, and are clumsy 

 and shapeless, covered with tubercles. Their pectoral 



