BY SAMUEL GARMAN. 49 



end of snout. Mouth cleft very deep, slightly curved, 

 extending as far back as the skull. Roof and floor of 

 mouth covered with sharp scales, the former curving up- 

 ward very strongly behind the teeth between the nostrils. 

 Upper and lower jaws about equal in length. Lips without 

 a groove or labial fold. Glossohyal cartilage (basihyal) 

 prominent above the floor of the mouth and free at its ex- 

 tremity about half an inch, forming a tongue. Teeth 

 small, similar in both jaws, several in each row in function 

 at the same time, each with three long, smooth, curved, 

 backward directed, slender, very sharp cusps each of 

 which bears some resemblance to a serpent's tooth. A 

 small cusp on the base at each side of the central. Bases 

 of teeth broad, extending inward about the length of the 

 cusps, terminating in two prongs (see fig.) which, extend- 

 ing beneath the base of the next tooth, prevent the possi- 

 bility of reversion or turning the cusps forward. Fourteen 

 rows of teeth on each side on the tipper jaws, no median 

 series. A median row on the symphysis of the lower jaws, 

 its teeth similar in size and shape to those of the thirteen 

 rows on each side of it. Hyomaudibular and ceratohyal 

 closely and somewhat firmly connected with the jaws at 

 the hinge or hinder angle of the latter. Branchial arches 

 long, very slender, with sharp small scales on their inner 

 edges. Without dissecting, twenty-two branchial rays can 

 be counted on the hyomandibular and ceratohyal (the first 

 arch) and on the succeeding six arches, in order, 15, 14, 

 12, 9, 6, and respectively. In most cases the outer ex- 

 tremities of the rays are produced in a sharp flexible point 

 beyond the adjacent margin of the gill covers. Gill open- 

 ings very wide, oblique, the opposite series very narrowly 

 separated on the throat, the fourth in front of a vertical 

 from the pectoral and the fifth and sixth extending back 

 above the shoulder. A broad opercular flap covers the first 



ESSEX INST. BULLETIN, VOL. XVI. 4 



