DISCUSSION OF SPECIES AND THEIR DISTRIBUTION. .">1"> 



II. Caudal not folly differentiated, and often confluent. 



A. Ventrals inserted on isthmus, nol far from humeral symphysis Bythitin i 



1. Pectorals simple. Byes present. 



a. Lateral line present posteriorly, 1ml broken in middle. 



i. Palatines dentigerous. Ventrals a pair of lilaments, each of two closely united rays. 



I ; j 1 1 1 1 1 1 - 

 ii. Palatines toothless. Ventrals a pair of simple rays Grammonus 



b. Lateral line obsolete poBtei iorlj . 



i. Ventrals a pair of simple rays. 



* Lateral line- distinct on front of body. 



t Palatines with teeth. Preoperculum unarmed. 



a. Head scaly (except -i i i. Lateral line indistinct. 



1. Operculum with a single spine. Venl median c.\ i i rv\ 



is. Head naked. Lateral line on trunk only. 



1. Operculum without aspine. Vent postmedian Saccogastek 



2. Operculumwithtwospines. Ventpremedian .. . .Diplacanthopoma 

 tt Palatines with teeth, Preoperculum strongly armed. 



a. Head partially naked. Lateral line obsolete posteriorly. 



1. Operculum with one spine, preoperculum with :i-4 Dicromita 



• Lateral line obsolescent , almost or (|iiite invisible. 

 t A feeble spine on the operculum. 



a. Head smooth. Eyes small 1; \ss, i/i m - 



li. Head crested. Eyes largo GLYPTOPHIDIUM 



1 1 Acute spines on head-bones and opercles. 



a. A long, tapering tail. No pyloric caeca DERM inu:i s 



ii. Ventrals a pair of bifid rays. 



* Caudal rays exserted, but confluent with those of anal and caudal. 



t Head scaly. 



A. Preoperculum with small spines at its angle. 



1. ( Iperculum with one spine Nkobtthites 



u. Preoperculum unarmed. 



1. Two spines ou operculum. Ventrals close together. Benthocometes 



2. One strong spine on operculum. Ventrals far apart BassogiGas 



C. Preoperculum with crenulated limb. 



1. Ventrals feeble, close together AXCOCKIA 



tt Head nak.nl. 



A. Lateral line not distinguishable. 



1. Several strong spines on head Celema 



n. Lateral line represented by a few large scales near shoulders. 



1. Head smooth. Tail very attenuate McEBIA 



Cauda] not continent with vertical (ins. but without distinct peduncle. 

 t Teeth on jaws, vomer and palatines in villiform bands. 

 a. Preoperculum unarmed. Head scaled. 



1. A flat opercular spine. 



a. Snout much produced and dilated. Lateral line very indistinct 

 (or absentf) Barathrodemus 



2. Operculum with a bony ridge above, ending in a blunt point. 



a. Snout not produced, broad, rounded, flattened at tip. Lateral 

 line obsolete posteriorly PYCNOCR 'SFEDUM 



3. Operculum a triangular flap, unarmed. 



a. Lower pectoral rays prolonged, the lowest filamentous. 



Nematonus 



c. Lateral line represented by three rows of pores, dorsal, lateral, and ventral. 



i. Head spinigerous. 



•Ventrals each of two distinct rays. < Opercular spine moderate, straight. Porogadi s 

 " Ventrals each of two united rays, i tpercular spine strong, curved Penopds 



2. Pectorals simple. Eyes absent or rudimentary. 



n. Body scaly. Eyes absent. 



i. Ventrals bifld lilaments. Teeth on jaws, vomer, and palatines Tatjredophidium 



3. Pectorals with lower rays differentiated. 



a. Preoperculum armed with three spines, operculum with one. Lateral line obsolete pos 



let iorly. 



i. Ventrals simple, not close together Pteri eras 



ii. Ventrals bifid, approximate Di< RO] I ffl 



