VIVIPAROUS FISHES OF THE PACIFIC COAST. 
383 
Description of family of Embiotocidce. — Viviparous teleosts with united lower 
pharyngeals; paired nasal openings; dorsal tin single, with 8 to 18 spines; a sheath of 
scales along the base of part of the dorsal, separated from the scales of the sides by 
a naked line; anal with three spines, its form differing in the sexes of some species; 
ventral fins thoracic, I, 5. No teeth on vomer or palatines; teeth in jaws small, some 
of those on pharyngeals larger, conical or paved. Pseudobranchiaj. No pyloric coeca. 
Oviduct opening behind the vent. 
Common characters. — Body compressed, oblong. Cheeks, operculum, and inter- 
operculum scaly; scales mostly cycloid. Lateral line arched, continuous. Mouth 
small, terminal; upper jaw protractile. Maxillary without supplemental bone. Gill 
membranes free from the isthmus. 
ANALYSIS OF THE GENERA OF EMBIOTOCIDCE. 
a. Dorsal spines 8-1 1 ; anal spines graduated (Embiotocince.) 
6. Abdominal vertebrae 17; caudal 19; anal basis much shorter than the abdomen; A. in, 23; lips 
large, lower lip with a frenum ; gill-rakers slender, short (7 — (- 13 ) ; anterior and 
lateral teeth of pharyngeals.small, bluntly conic; a triangular posterior patch 
of larger teeth, all but the posterior row truncate, the posterior row conic. 
Hypsurus, 1. 
66. Abdominal vertebras 13-15 ; anal basis equaling, or longer than, the abdomen, 
c. Teeth entire, usually bluntly conic. 
d. Dentiferous surface of lower pharyngeals arched, the anterior teeth much worn, the posterior 
not at all, the cutting surface of the anterior teeth flattened, that of the poste- 
rior teeth not faced. Teeth of the upper pharyngeals similar to those of the lower 
pharyngeals, but the posterior teeth of the upper pharyngeal applied to the an- 
terior of the lower pharyngeal; the posterior teeth of the upper pharyngeals thus 
resemble the anterior of the lower pharyngeals and the anterior of the upper the 
posterior of the lower Damalichthys, 2. 
dd. Dentiferous surface of lower pharyngeals flat or concave. 
e. Teeth in two -series in each jaw. Male with one of the anterior rays of the anal transformed 
into a triangular plate ; anal basis forming a decided angle at this point ; the rays 
in front of this point with a thick covering of skin ; pharyngeal teeth mostly 
small, conic, only a few in the last two series enlarged, some of which are some- 
times truncate molars. 
/. Vertebrae 33-35; lower lip without a frenum; gill-rakers very long, slender, and tapering, 
23 to 29; anal basis below 12-14 caudal vertebrae Hyperprosopon, 3. 
ff. Vertebrae 32 (14 + 18) ; lower lip without a frenum; gill-rakers moderate, stout, blunt, 
6 + 11 ; anal basis below 11 caudal vertebrae Holconotus, 4. 
fff. Vertebrae 29 (13 + 16); lower lip with a broad frenum; gill-rakers short, stout, hlunt, 
5 + 11; anal basis below 10 caudal vertebrae Amphistichus, 5. 
ee. Teeth none, or in a single series in each jaw, anterior and lateral pharyngeal teeth small, 
conic, the median and posterior ones large, truncate, molars ; males with a gland 
on some of the anterior anal rays, the anal basis without angle, none of the rays 
modified to form a definite plate. 
g. Teeth none, lips thin; jaws greatly protractile Neoditrema, 7. 
gg. Teeth in both jaws. 
6. Dower lip very thick, lobed, without a frenum ; gill-rakers long Rhacochilus, 6. 
lih. Lower lip thin, normal, entire, with a frenum. 
i. Scales small, 60-75 in lateral line. 
j. The characters of Ditrema should he added fiere. No examination of internal 
organs has as yet been made Ditrema, 8. 
k. Vertebrae 14 + 18 or 19, anal basis below 9 caudal vertebrae; first haemal spine 
small, applied to the second Embiotoca, 9. 
