Brotulids Killed by 1950 Eruption — Gosline 
granular, some sharply conical. No teeth on 
tongue or branchial arches. Lower pharyngeal 
tooth-patches widely separated. Premaxillary 
bands separated by a slight interspace at 
symphysis. Vomerine teeth in a continuous, 
narrow band. Palatine band very narrow, prac- 
tically two-rowed. Tongue a short, blunt 
knob, which does not extend as far forward 
as the vomer. Slit behind fourth gill arch very 
small. Pseudobranch represented by a pair of 
minute filaments on one side, but apparently 
absent on the other. 
Lateral line composed of small papillae that 
penetrate the scales at intervals; in two sec- 
tions, the anterior straight and well dorsal on 
the back to about the level of the anus, the 
posterior mid-lateral from above the anal ori- 
gin to the end of the body, becoming less 
prominent posteriorly. 
Dorsal originating nearly an eye diameter 
behind the pectoral axil, the rays, as in the 
anal, increasing gradually in length to near 
the tail. Dorsal and anal with a scaleless basal 
sheath of skin which covers the greater part 
of each of the first rays but which decreases 
in width posteriorly, terminating slightly 
ahead of the tail. 
Pectorals with the rays graduated in such 
a way as to give the fin a somewhat tapering 
point above the middle. Base of pectoraTfin 
with a scaleless, lobate sheath which con- 
trasts strongly with the scaled lobe from which 
the pectoral base projects. Pelvics originating 
approximately under the lower point of the 
opercle, each of a simple filament which is 
apparently composed of two fused rays. 
Copulatory lobe present (Fig. if). Air blad- 
der present. 
Body brownish. Head and fins bluish black. 
The specimen described above appears to 
differ from D. hrachysoma Gunther (1887: 115) 
in a number of minor respects. D. hrachysoma 
is said to have the eye equal to the interorbital 
width; the specimen at hand has the eye con- 
siderably less than the interorbital width. 
(However, the Hawaiian specimen is consid- 
erably larger than the type and only specimen 
75 
of Gunther’s species.) Also, the dorsal fin of 
D. hrachysoma seems to originate farther for- 
ward than that of the Hawaiian specimen, and 
no basal, fleshy sheaths along the dorsal and 
anal are described or figured for D. hrachysoma. 
D. rwers-andersom Alcock (1895: 144) is the 
second species to be described in the genus. 
Though there are several descrepancies be- 
tween Alcock’s description and plate and the 
specimen at hand, I can find none that seem 
to be of certain specific validity. Alcock’s 
plate shows enlarged scales along the front of 
the lateral line, but, as most of the scales in 
Alcock’s specimen appear to have been lack- 
ing, I am not sure that this is not an artist’s 
artifact. The head of the Hawaiian specimen 
appears to be somewhat larger (but Alcock’s 
specimen was larger), and there is no scaleless 
membrane figured or described on the base 
of the pectoral fin of D. rivers-andersoni. (As 
in D. hrachysoma, no fin-ray or scale counts 
are given for Alcock’s species.) 
From D. hrunnea Smith and Radcliffe (Rad- 
cliffe, 1913: 167), the Hawaiian specimen dif- 
fers distinctly in the more numerous fin rays. 
D. raniceps Alcock (1898: 154), D. alcocki 
Goode and Bean (1895: 528), D.jordam (1899: 
160), and D, nigripinnis Gilchrist and von 
Bonde (1924: 20) are inadequately described 
species about which little can be said. 
Diplacanthopoma (sp..^) 
Tables 1, 2; Figs. Ic-e, 2h, ^h 
MATERIAL EXAMINED: 1 male, 135 mm. in 
standard length, collected off the Mauna Loa 
lava flow, Hawaii, by Moore et al., June 3, 
1950. 
This specimen has a regenerated tail, and 
its standard length, lateral line scale count, 
and dorsal and anal count are consequently 
all abnormal, i.e., too low. In general, the 
specimen is in a better state of preservation 
than that of D. {rivers-andersoni?) , with fewer 
scales lost, the mucous sinuses on the head 
and the fleshy sheaths at the bases of the fins 
less bloated, etc. The fish, however, has died 
with the gill covers widely flaring and the 
