672 Gobioidei, Discocephali, and Tzniosomi 
Of the typical gobies having the ventrals united we can 
mention but a few of the myriad forms, different species being 
Fic. 583—Guavina mapo, Dormitator maculatus (Schneider). Puerto Rico. 
abundant alike in fresh and salt waters in all warm regions. 
In Europe Gobius jozo, Gobius ophiocephalus, and many others 
Fic. 584 —Vireosa hane Jordan & Snyder. Misaki, Japan. 
are common species. The typical genus Gobins is known by 
its united ventrals, and by the presence of silken free rays on 
Fic. 585.—Esmeralda de Mar, Gobionellus oceanicus (Pallas). Puerto Rico. 
the upper part of the pectoral fin. Mapo soporator swarms 
about coral reefs in both Indies. Gobionellus oceanicus, the 
