Monogenetic Trematodes, I — Yamaguti 
85 
stem 0.4— 0.6 mm long, and its right arm cross- 
ing ovary at about its middle. Vagina entirely 
lacking. 
DISCUSSION : This new genus differs from Al- 
lop seudaxine Yamaguti, 1943, in the complete 
absence of vaginae and the presence of cuticu- 
larized apical thickenings of clamp capsule be- 
neath the apical ends of dorsal and ventral lateral 
sclerites. 
Unnithan (1957) proposed a new genus 
Uraxine which is now regarded as a synonym of 
Allop seudaxine Yamaguti, 1943, and placed it in 
his new subfamily Monaxininae of his family 
Axinidae. Price (1962) created a new family 
for Allop seudaxine; but I prefer to assign this 
genus, along with the present new genus, to Allo- 
pseudaxininae Yamaguti, 1963, of Unnithan’s 
Axinidae. 
Allop seudaxinoides n. g. 
GENERIC DIAGNOSIS: Axinidae, Allopseudax- 
ininae. Body large, abruptly tapering anteriorly, 
Opisthohaptor unilateral, oblique; clamp skele- 
ton consisting of a median U-shaped spring, a 
pair of dorsal lateral sclerites and a pair of ven- 
tral lateral sclerites; ventral lateral sclerite articu- 
lating with dorsal lateral sclerite at the angle 
where the latter turns medially. This pattern of 
clamp skeleton is exactly similar to that of Allo- 
pseudaxin-e, only differing from the latter in hav- 
ing paired sderotized thickenings at the apex of 
clamp capsule beneath apex of dorsal and ventral 
lateral sclerites. Caudal appendage bearing two 
pairs of anchors. Esophagus bifurcating a short 
distance posterior to genital pore. Intestinal 
limbs with numerous side branches, terminating 
near base of terminal appendage. Testes not 
very numerous pie , para-, and postovarian. 
Genital atrium sucker-like, provided inside with 
a corona of apically curved spines, at the base of 
which is another circle of denticles supporting 
the spines. Ovary tubular, turned back on itself 
in midregion of body. Eggs elliptical, with fila- 
ment at each pole. Vaginae absent. Vitellaria 
co-extensive with intestine and its branches; 
vitelline reservoir Y-shaped, sinistral to ovary. 
Parasitic on gills of marine teleosts. 
TYPE SPECIES: A, euthynni n. §p., on Euthyn- 
nus yaito; Hawaii. 
15. Allomonaxine carangoides n. g., n. sp. 
Fig. 16 
HABITAT: Gills of Carangoides sp.; Hawaii. 
HOLOTYPE: U. S. Nat. Mus. Helm. Coll, S.Y. 
No. 15. 
DESCRIPTION ( based on 9 whole mounts ) : 
Body moderately large, wedge-shaped in outline, 
tapering anteriorly, widest (0.2-0.27 mm) at 
the obliquely truncated posterior end, along 
which is attached a row of 40 to 50 clamps. 
Clamp skeleton up to 70-110/* wide, of Micro- 
copy le type, consisting of a U-shaped median 
piece without accessory apical pieces, two pairs 
of lateral sclerites and a pair of curved basal 
rods. Head end truncate, 0. 3-0.4 mm wide, with 
wide ventroterminal mouth aperture. Oral suck- 
ers elliptical, septate, 0.08-0.11 X 0.15-0.2 mm. 
Pharynx pyriform, 57-100 X 47-63/x; esophagus 
0.3-0. 5 mm long, with few side branches, bifur- 
cating immediately behind genital atrium. In- 
testinal limbs with numerous, subdivided, outer 
branches and fewer, simpler, inner branches, not 
confluent posteriorly; left limb extending be- 
yond right limb to near extreme left end of body. 
Testes rounded, very numerous, paved in one 
layer and occupying whole postovarian inter- 
intestinal field; under low power of magnifi- 
cation they appear like a single lobed organ 
subdivided by inner intestinal branches. Vas 
deferens winding regularly from one side of 
median line to the other among inner intestinal 
branches, convoluted behind intestinal bifurca- 
tion. No cirrus differentiated. Genital atrium 
reniform, 0.16-0.24X0.24-0.27 mm, provided 
with well-developed radial muscle fibers, armed 
inside with spines of four different types; ven- 
tral spines 30-75/* long, 34-40 in number, with 
straight shaft and clawlike point, arranged very 
dose to one another in a transverse row inter- 
mingled dorsally at somewhat regular intervals 
with 14-16 shorter spines whose point is simple 
and whose shaft is outcurved dorsally about the 
middle; of the lateral spines four lie transversely 
on each side at the male genital pore, and 20- 
22, similar in shape to those longer ventral 
spines and 50-63/* long, are arranged in a 
gently curved row immediately lateral to the 
shorter (30-40/* long), stouter claw-like, medial 
FIG. 15. Allopseudaxinoides euthynni n. g., n. sp. 15 A, Holotype, ventral view; 15B, clamp, dorsal view; 
15C , caudal anchors; 15D, terminal genitalia, ventral view; 15E, egg. 
