CHAPTER XXVI 

 GOBIOIDEI, DISCOCEPHALI, AND TvENIOSOMI 



UBORDER Gobioidei, the Gobies: Gobiidae. The great 

 family of Gobiidce, having no near relations among 

 the spiny-rayed fishes, may be here treated as form- 

 ing a distinct suborder. 



The chief characteristics of the family are the following: 

 The ventral fins are thoracic in position, each having one spine 

 and five soft rays, in some cases reduced to four, but never 

 wanting. The ventral fins are inserted very close together, 

 the inner rays the longest, and in most cases the two fins are 

 completely joined, forming a single roundish fin, which may be 

 used as a sucking-disk in clinging to rocks. The shoulder-girdle 

 is essentially perch-like in form, the cranium is usually depressed, 

 the bones being without serrature. There is no lateral line, 

 the gill-openings are restricted to the sides, and the spinous 

 dorsal is always small, of feeble spines, and is sometimes 

 altogether wanting. There is no bony stay to the preopercle. 

 The small pharyngeals are separate, and the vertebrae usually 

 in normal number, 10+14 = 24. 



The species are excessively numerous in the tropics and 

 temperate zones, being found in lakes, brooks, swamps, and 

 bays, never far out in the sea, and usually in shallow water. 

 Many of them burrow in the mud between or below tide-marks. 

 Others live in swift waters like the darters, which they much 

 resemble. A few reach a length of a foot or two, but the most 

 of the species rarely exceed three inches, and some of thme 

 are mature at half an inch. 



The largest species, Philypnus dormitor, the guavina de 

 rio, is found in the rivers of Mexico and the West Indies. 

 It reaches a length of nearly two feet and is valued as 

 food. Unlike most of the others, in this species there are 



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