32 
PACIFIC SCIENCE, VoL XXII, January 1968 
mediately dorsal to ventral medullary excretory 
anastomoses, in one layer or two; although their 
total number could not be determined, they 
are not numerous. Thin-walled vas deferens 
convoluted around base of cirrus pouch. Cirrus 
pouch subglobular, 0.16-0.2 mm X 0.13-0.2 
mm, not very muscular, situated in median 
field, with its long axis nearly at right angles 
to body surface, containing somewhat muscular 
pars prostatica surrounded by prostate cells at 
its base and an axial cirrus, which is lined with 
corrugated cuticle and supported by numerous 
transverse muscle fibers. The distal end of the 
cirrus joins the vagina to form cirrovaginal 
pore which opens at the bottom of the mid- 
dorsal notch by a comparatively wide aperture. 
Ovary arcuate, multilobulated, median, elon- 
gated transversely at base of proglottis, with 
its lateral ends curved posteriad or dorsad, 
0.25-0.35 mm wide, up to 0.8 mm wide when 
extended; in cross sections a short lobe or two 
may be seen in the dorsal concavity of the ovary, 
where the vagina joins the germiduct arising 
from the dorsoposterior concave margin of the 
ovary. Vagina lined with thick cuticle and 
surrounded by dense layer of gland cells, run- 
ning dorsad and backward windingly, opening 
into cirrovaginal pore alongside cirrus pouch. 
Vitelline follicles arranged in one layer all 
around between cortex and medulla, interrupted 
at notches where the uterus and cirrovaginal 
pore open, but continuous from proglottis to 
proglottis. Uterus winding a few times in 
median medulla from right to left and vice 
versa, not reaching to lateral medulla, distended 
with eggs when gravid, opening at small mid- 
ventral notch at about level of cirrovaginal pore 
(Fig. 6C). No uterine sac. Eggs subglobular 
to ovoid, not operculate, 34-5 Ip X 23-37p 
in lactophenolglycerine jelly, relatively thick- 
shelled, each containing oncosphere. 
discussion : This genus differs from the 
most closely related Ptychobothrium Loennberg, 
1889, as follows: (1) bothrial edges are mark- 
edly crenulated; (2) the inner longitudinal 
muscle layer is divided by the vitellarian layer 
into two (outer and inner) layers; in Ptychobo - 
t hr turn the longitudinal muscle- bundles are 
seen among or between the vitelline follicles, 
but not divided into two layers; (3) the vagina 
is very strongly developed and so long that it 
forms transverse windings; (4) the multilobu- 
lated ovary is curved dorsoposteriad at its lateral 
ends to form a conspicuous dorsal concavity; 
(5) the uterus does not extend as far laterad as 
in Ptychobothrium and does not form a uterine 
sac; (6) the uterine pore is midventral instead 
of submedian. 
Recently, Cable and Michaelis described in 
the Proceedings of the Helminthological So- 
ciety of Washington 34(1) : 1 5—17, 1967, a new 
cestode, Plkatobothrium cypseluri n. g., n. sp., 
from the Caribbean flying fish, Cypselurus 
hah ten sis. This worm resembles Alloptychobo- 
thrium spilonotypteri very closely, especially in 
the general shape of the scolex, the structure 
of the terminal genitalia, and the position of 
the vi cellar ia between the outer and inner layers 
of the longitudinal muscle bundles, but differs 
distinctly from the latter in that the ovary is 
V-shaped in dorsoventral view and the gravid 
uterine sac is conspicuously Y-shaped. The two 
species might be referred to the same genus, 
but until a detailed comparison of them is made 
on the whole mounts and sections, I prefer to 
regard them for the present as distinct not only 
specifically but also genetically. 
Alio ptychobothrium n. g. 
generic diagnosis: Ptychobothriidae. Scolex 
arrowhead-shaped in lateral view, compressed 
from side to side, with dorsal and ventral 
bothrial edges markedly crenulated. Neck ab- 
sent. Strobila may be completely or incompletely 
segmented; proglottides wider than long, craspe- 
dote or not. Inner longitudinal muscle bundles 
divided by vitellarian layer into two (outer and 
inner) layers. Testes not numerous, in one layer 
or two, in submedian ' medulla immediately 
dorsal to ventral medullary excretory anasto- 
moses. Cirrovaginal pore opening at bottom of 
middorsal notch. Ovary multilobulated, arcuate, 
transversely elongated, median, at posterior end 
Figs. 6A-D. Alloptychobothrium spilonotopteri n. g., n. sp. A, scolex of holotype, lateral view; B, ma- 
ture proglottis of paratype, dorsal view; C, transverse section of gravid proglottis of paratype through cirrus; 
D, transverse section of gravid proglottis of paratype through ovary. 
