Phoxocephalidae — BARNARD 
147 
Trichophoxus) but the writer has found species 
which intergrade between the broad and nar- 
row rostral types. However, it is useful to 
separate the two groups as subgenera, using 
the names Paraphoxus s.s. (broad rostrums) 
and Trichophoxus (narrow rostrums) . 
SPECIFIC CRITERIA IN THE GENUS PARAPHOXUS 
Much of the apparent confusion in phoxo- 
cephalid systematics stems from the super- 
ficial lack of specific criteria. It is often the 
case that two species may appear quite similar 
with respect to head, gnathopods, peraeopods, 
uropods, and third epirnera, which are the 
characters most useful systematically in other 
amphipods. Additional specific differences 
have been sought and one of the most im- 
portant of these is the condition of the epis- 
tome. The presence of an acutely produced 
epistome in one of a pair of otherwise similar 
species has been most useful in calling atten- 
tion to their distinctness and to a need for 
statistical measurement of other minor dif- 
ferences. Pontharpinia epistoma Shoemaker, 
1938, was the first phoxocephalid described 
with a produced epistome. In the materials 
at hand are nine other new species bearing 
produced epistomes of varying extent, several 
of which are otherwise scarcely distinguish- 
able from relatives in which the epistome lacks 
an anterior process. 
Unfortunately, many of the existing specific 
descriptions of paraphoxids are practically 
useless and all species should be re-examined 
according to the following list of criteria. 
Due to the fact that seemingly minute differ- 
ences may have specific value, drawings are 
far more useful than words. 
The criteria deemed important by the writer 
and for which figures should be drawn are: 
1. Dorsal shape of head and rostrum. 
2. Size of eyes in both sexes in relation to 
size of head. 
3. Shape of epistome from lateral view. 
4. Presence or absence of a distal spine or 
claw on palp article 4 of the maxilliped. 
5. Shape and size of articles 5 and 6 in both 
pairs of gnathopods. 
6. Stoutness of spination on article 5 of 
peraeopods 1 and 2. 
7. Unusual features of the coxae. 
8. Ornamentation and proportions of the 
articles of peraeopods 3, 4, and 5. 
9. Configuration and armature of pleonal 
epirnera 2 and 3. 
10. Spination of uropods 1 and 2. 
11. Proportions of uropod 3. The length 
of the inner ramus on the female is quite 
variable interspecifically, as is the length and 
shape of article 2 of the outer ramus. 
12. Breadth, apical shape, and armature of 
telson. 
13. Breadth and dorsal depression of body. 
Paraphoxus milleri (Thorsteinson), 
new combination, new synonymy 
Pontharpinia milleri Thorsteinson, 1941: 82. 
Pontharpinia longirostris Gurjanova, 1938: 263 
( = Homonym, not Schellenberg, 1931). 
Pontharpinia robusta Gurjanova, 1938: 262 
( = Homonym, not Holmes, 1908). 
A study of the variability of this species in 
eastern Pacific waters indicates that the names 
above should be fused. Both of the earlier 
names of Gurjanova are junior homonyms so 
that the only available name is P. milleri. 
Paraphoxus obtusidens (Alderman), 
new combination, new synonymy 
Pontharpinia obtusidens Alderman, 1936: 54. 
Pararpinia (sic) pontarpioides Gurjanova, 1953: 
229. 
The description and figures of the junior 
synonym represent one form of this variable 
northern Pacific species. 
Paraphoxus sinuatMS (K. H. Barnard), 
new combination, new synonymy 
Parharpinia villosa , Schellenberg, 1931: 75 
(not Haswell, 1879). 
Parharpinia sinuata K. H. Barnard, 1932: 103- 
104, fig. 52. 
