23.2 H err e: Philippine Eels 227 



brown marblings, which usually form more or less definite trans- 

 verse bands, especially on tail ; belly and throat paler, the mark- 

 ings there much reduced or forming only irregular spots and 

 marks; on the head they may fuse so that the ground color 

 merely shows as more or less stellate spots on sides; no dark 

 patch at angle of mouth, though inside of mouth is often marked 

 with dark flecks; no dark patch around gill openings. 



In alcohol the colors are usually much duller, the ground color 

 ordinarily becoming brownish or yellowish and the markings 

 sometimes nearly or quite obsolete. Occasionally specimens are 

 mottled with light and dark, the vertical crossbands and reti- 

 culations but little evident. 



This species is common in the Philippines, and in the coral 

 sand beaches at Sitanki and at similar localities it swarms in 

 countless numbers. I have examined numerous specimens, rang- 

 ing in length from 150 to 322 millimeters, collected at Sitanki, 

 Davao, Dumaguete, Cabalian on Leyte Island, Caldera Bay, 

 Mindanao, and Puerto Galera, Mindoro. It has been recorded 

 from reefs near Cebu, by Giinther; from San Fabian, Pangasi- 

 nan, by Evermann and Seale ; and from Sibuyan, by Jordan and 

 Richardson. The last named state their specimen had "corner 

 of mouth with a dark streak, above and below (in front) which 

 is a larger pale spot." I have a specimen 290 millimeters long 

 from Cabalian, Leyte, which agrees in the main with Gymno- 

 thorax richardsoni but has a small dark streak at corner of 

 mouth. It is probable that this mark does occur, though rarely, 

 in this species. In body color and general appearance this eel 

 is often indistinguishable from certain other species, such as 

 pictus, chilospilus, and undulatus, so that it is very difficult to 

 arrive at a definite conclusion with regard to certain specimens, 

 especially where the species is so variable as is the present one. 

 From pictus it may easily be separated by the long fangs on the 

 intermaxillary plate, but when the colors and markings are 

 faded it may be impossible to separate it from the other two. 

 The presence of so-called scale pouches on the skin, formed by 

 the crisscrossing of skin folds, is a character strongly stressed 

 by certain authors, but it occurs in so many species that I have 

 not used it as a diagnostic character and attach no particular 

 importance to it. This species has a rather compressed form, 

 is of small or medium size, not reaching a meter in length, and 

 in life is one of our handsomest eels. It is very widespread, 

 occurring from Zanzibar and Socotra to the Philippines, Aus- 

 tralia, and the islands of the South Pacific. 



