292 Macueay Memoria Vouume, 
one-fourth as wide as the body. The tail is nearly hemispherical. From the incon- 
spicuous vulva the vagina, which is one-half as long as the body is wide, leads into 
two long uteri, in either of which the eggs are arranged in several rows. The anterior 
uterus is so long that the flexure in the oviduct sometimes lies in front of the cardiac 
region,—something uncommon in free-living nematodes. Supposing the specimens 
observed to have been mature, the sub-spherical eggs had a diameter one-fourth as 
great as the diameter of the body. Figured on Pl. xu. 
Hab.—The young were common about the roots of banana plants in Fiji, July, 
1891. But few adult females were seen, and no males. 
‘t 776 25°6 ‘54” 98° © s s 
Sos 2ssmm. ~The cuticula is thick and transparent. 
4. D. perfectus, n.sp. 
The neck is conoid, becoming convex-conoid near the head, which is truncate and 
bears six distinct doubly-papillate lips of the usual form. The well developed spear 
is one-fifth as wide as the head and slides in a distinct close-fitting collar, situated 
just behind the lips. The anterior part of the esophagus is only one-fourth as wide 
as the corresponding part of the neck, but at the middle it enlarges rather suddenly 
and becomes two-fifths as wide as the body, its component cells being of such a size 
that ten side by side make up a circumference, and having their granular contents so 
disposed as to give rise to a distinct polygonal tessellation. The rectum is twice as 
long as the anal body-diameter. The pre-rectal portion of the intestine is about four 
times as long as the anal body-diameter, or in the males, twice as long as the spicula. 
The intestine is three-fourths as wide as the body. In the neck at least two 
unicellular glands were observed; each of these was as long as the neck was wide and 
emptied laterally (or sublaterally) by means of an indistinct ampulla and short narrow 
distinct chitinous pore which plainly penetrated all the cuticular structures at a 
distance from the head equal to five per cent. of the length of the body. The vulva 
is not conspicuous. The eggs are one and one-half times as long as the body is wide, 

three-fifths as wide as long. 334-373 = * essmm. The tail of the male, like that of 
the female, is rounded, and bears the four sub-median papillze, also found in the female. 
A single ventral row of about twenty-three innervated closely approximated low papillze 
are found opposite the ductus ejaculatorius, that is to say, begins just in front of the 
spicula and extends nearly to the anterior extremity of the pre-rectal portion of the 
intestine. One such papilla stands alone just in front of the anus. Seen in profile 
the spicula are boomerang-shaped. They are acute, and are stiffened anteriorly by a 
median thickening. The proxime are not cephaloid. Accessory pieces are apparently 
wanting. The spicula are very likely exserted by means of muscles passing obliquely 
to the extremity of the tail. Oblique copulatory muscles are present throughout the 
region of the ductus. Figured on Plates xt. & X11. 
