THE BULLHEADS AND GURNARDS 



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which are also found on this side of the Atlantic, as well as two other less common 

 species. The males of the common marine species are stated to build a nest of 

 stones and seaweed for the reception of the spawn; and to guard and defend the 

 young fry when hatched. 



On the Indian and Australian coasts the bullheads are represented by the 

 so-called flat heads or crocodile fishes (Platycephalus} in which the much depressed 

 head is more or less fully armed with spines, and the body covered with ctenoid 

 scales; the anterior spine of the first dorsal fin being isolated from the rest, and 



COMMON BULKHEADS 



(Natural size.) 



teeth present on both the vomer and palatine bones. Day writes of these fishes 

 that ' ' the wounds from their spines are dreaded because of the violent irritation 

 they occasion. Their eyes are peculiar; the iris possesses two semi-circular flaps, 

 one above, the other below, the upper being usually the larger; these flaps can be 

 brought close together, probably under the stimulus of light." 



Of a decidedly ugly appearance, the gurnards (Trigla) are easily 

 recognized by their enormous, square, and elevated heads, in which 

 the upper surface and sides are entirely bony, and likewise by the finger-like first 

 three rays of the pectoral fins, which serve not only for walking on the sea bottom 



Gurnards 



