34 
PACIFIC SCIENCE, Vol XXII, January 1968 
of proglottis. Vitellaria continuous laterally and 
from proglottis to proglottis, but interrupted at 
notches, where the uterus and cirrovaginal pore 
open outside. Uterine coils confined to median 
field dorsal and anterior to ovary, not forming 
uterine sac before opening midventrally; eggs 
not operculate, containing subglobular onco- 
sphere. Ventral longitudinal excretory stems 
anastomosing with narrower ventral vessels run- 
ning longitudinally lateral to them. Parasitic in 
marine teleosts. 
type species: A , spilonotopteri n. sp., in 
Cypselurus spilonotopterus; Hawaii. 
lecanocephalidae Braun, 1900 
7. Cephalobothrium aetobatidis Shipley et 
Horne!.!, 1906 
Fig. 7 A—D 
habitat: Spiral valve of Aetobatis nartnan; 
Hawaii. 
description (based on five immature speci- 
mens and a single mature specimen) : Strobila 
18.7 mm long in the mature specimen, com- 
prising 144 craspedote segments; some of the 
posterior segments were detached during prep- 
aration of the whole mount. Scolex rounded 
quadrangular, 0.5 X b-^7 mm > occupied at its 
apex by a circular muscle pad 0.45 X 0-5 mm 
and dome-shaped in profile. The strong muscle 
bundles of the pad are converged toward the 
center, without forming a suctorial depression 
or lumen; these muscle bundles are continued 
backwards into the ensuing proglottides in form 
of inner longitudinal bundles delimiting the 
medulla from the cortex. Around the apical 
pad is a circular collar-like fold which is con- 
spicuous in much younger individuals. The 
four suckers situated at the corners of the scolex 
are 0.13 mm in diameter and present typical 
suctorial structure. Neck absent. Immature and 
anterior mature proglottides wider than long, 
but posterior mature ones longer than wide, 
constricted at both extremities. The easily 
detachable posterior proglottides are elliptical, 
0. 5-0.8 mm X 0.4-0.55 mm, with the posterior 
end produced backward in form of an abruptly 
tapering truncate cone. The inner longitudinal 
muscle bundles are strongly developed in the 
anterior immature proglottides but, as they 
proceed backward, they become gradually thin- 
ner and wider apart one from another, and in 
the posterior mature proglottides they are re- 
duced to a layer of very fine individual fibers. 
Excretory stems not seen. 
Testes globular to oval, comparatively large 
(50-100p in diameter), 15-25 in number in 
mature proglottides, massed together, partly 
overlapping one another, in greater part of 
medulla between two lateral vitelline fields, 
leaving anteriormost and posterior parts of 
proglottis free. Vas deferens convoluted dose 
to medial end of cirrus pouch. Cirrus pouch 
elongate pyriform or short claviform, 0.19 X 
0.06 mm in the mature proglottis figured, lying 
transversely in pre-equatorial zone, nearly reach- 
ing median line, containing convoluted ejacula- 
tory duct surrounded by gland cells (Fig. 7C) 
at base and eversible tubular ejaculatory duct 
distally. Cirrus, when everted, cylindrical, 
smooth, 60[a X 2 Op in the proglottis figured 
(Fig. 7D), projecting backward along lateral 
margin of proglottis. Genital atrium is clearly 
seen, when the cirrus is not everted, as a arti- 
cular ring, into which the cirrus opens im- 
mediately in front of the vagina. The genital 
pore pre-equatorial, may be slightly depressed 
occasionally, alternating irregularly from side to 
side. 
Ovary two-winged, 0.1 X 0*3 mm in the 
mature proglottis figured (Fig. 7D), situated 
near posterior end of proglottis, with shell 
gland complex immediately behind its isthmus. 
Vitellaria follicular, extending in lateral me- 
dulla between testes and lateral edge of inner 
muscle sheath from a little behind level of 
anterior extent of testes to ovarian wings, where 
the transverse vitelline duct passes inward on 
each side. The winding uterine duct running 
forward dorsal to the ovarian isthmus appears 
to open into the incipient uterus proper from 
Figs. lA—D. Cephalobothrium aetobatidis Shipley et Hornell, 1906. A, scolex, apical view; B, same, lateral 
view; C, male terminalia, ovariovaginal complex, and seminal receptacle, dorsal view; D, end proglottis, dorsal 
view. 
