NO. 7 WADE: EASTERN PACIFIC APODAL FISHES 189 



Maxillary and mandibular teeth in narrow bands of small, pointed, 

 close-set teeth. Maxillary teeth united with slightly enlarged premaxil- 

 lary teeth, and closely approaching the vomerine teeth at the head of the 

 shaft of the vomer. Vomerine teeth in an elongate, triangular patch of 

 small, pointed, close-set teeth anteriorly, tapering to an irregular row of 

 conical teeth posteriorly. Vomerine teeth separated from premaxillary 

 teeth by a narrow semicircular interspace. 



Upper lip with a narrow, upturned labial flange. Labial canal present. 

 Inferior edge of labial canal expanded into a broad shield or winglike 

 plate, extending outward and downward to the oral edge of the upper lip. 



Thyreoconger most closely resembles Alloconger, but differs from that 

 genus in having the inferior edge of the labial canal expanded into a broad 

 shield or winglike plate, a more posteriorly inserted dorsal, and the tail 

 scarcely longer than the head and trunk. It also differs from Alloconger 

 in the size and position and shape of the premaxillary patch of teeth. In 

 Alloconger these teeth are in a large, conspicuous, circular patch, united 

 posteriorly to the maxillary and vomerine bands of teeth. In 

 Thyreoconger the premaxillary teeth are a continuation of the maxillary 

 bands around the tip of the upper jaw, and are separated from the 

 vomerine teeth by a narrow semicircular interspace. 



Thyreoconger hemiaspidus, new species 

 Plate 25, figs. 1-3 



Holotype. — AHF no. 461. 



Type locality. — Station 725-37, North of Point Lobos, Gulf of Cali- 

 fornia, Sonora, Mexico, dredged in 10 fms, March 26, 1937. 



Paratypes. — AHF no. 310. Station 767-38, 1 specimen, 105 mm, 

 Chacahua Bay, Oaxaca, Mexico, dredged in 40-50 fms, January 9, 1938. 

 — AHF no. 299. Station 769-38, 1 specimen, 103 mm, off San Jose 

 Point, Guatemala (13° 46'N, 91° 14'W), 20 fms, January 11, 1938. 



Measurements of holotype in mm. — Total length 158, depth 9.5, 

 head and trunk 77.5, tail 82.5, head 28, snout 5.5, eye 5.5, gape of mouth 

 7.5, gill-opening 3, isthmus 4, pectoral length 11, interorbital 1. 



Diagnosis. — Head and trunk 2.1 to 2.2 in total length, 1.09 to 1.2 in 

 tail. Tail 1.83 to 1.92 in total length. Head 5.6 to 6.2 in total length, 2.5 

 to 2.85 in head and trunk. Snout 4.75 to 5.1 in head, eye 4.8 to 5.5, gape of 

 mouth 3.7 to 3.9, pectoral length 2.54 to 3, gill-openings 8.25 to 9.39, 

 isthmus 6.8 to 7.5. Depth 16.6 to 18.1 in total length, 2.94 to 3.1 in head. 



