770 
Journal o f Agricultural Research 
Vol. XXX, No. 8 
about 80 by 50 m according to observa¬ 
tions of the present writer (fig. 16), 
which is in agreement with the size 
given by Travassos but is larger than 
that given by Lane (65 X 40 ju) • Since 
practically all of Lane’s measurements 
fall short of the present writer’s meas¬ 
urements, it may be concluded that no 
such actual discrepancy as regards the 
size of the eggs which Lane’s figures 
indicate really exists, the difference be¬ 
ing due in all probability to some slight 
fault in the calculation of measure 
ments. 
Fig. 15.—Vulva and vagina of Ascaridia lineata 
(original), v., vulva; vag. vagina 
JO/J 
Fig. 16.—Eggs of Ascaridia lineata (original) 
SPECIFIC DIAGNOSIS OF ASCARIDIA LIN¬ 
EATA SCHNEIDER, 1866 
Synonyms.—Heterakis perspicillum Von Linstow, 
1894 (misdetermination); Ascaridia hamia Lane, 
1914; H. braziliensis Magalhaes, 1892 (according to 
Travassos, 1913). 
Mature specimens 70 to 120 mm. long by about 
1 mm. or more wide, the females being larger than 
the males. Lips prominent, each lip provided with 
two papillae and a dentigerous ridge bearing distinct 
teeth. Oesophagus simple, from 3 to 4 mm. long 
by 0.34 mm. wide in adult specimens. The nerve 
ring is located approximately anterior to the first 
fourth of the oesophagus and the excretory pore is 
posterior to the nerve ring. 
Male.—T en pairs of papillae arranged in 3 
groups, as follows: An anterior group of 3 pairs of 
ventral papillae arranged on each side of the sucker, 
the middle pair of this group of papillae being along¬ 
side, the anterior pair being on the level with or 
anterior to, and the posterior pair being posterior to 
the sucker; a second group consisting of 3 pairs of 
lateral and 1 pair of ventral papillae, all being post- 
anal in position with occasional variations in which 
the first lateral papilla may be on a level with or 
somewhat anterior to the anus; a third group of 
2 pairs of lateral and 1 pair of ventral papillae in 
the region of the tip of the tail. Spicules, variable 
in size, minimum length 0.54 mm. in young forms 
and maximum length 2.4 mm. in adult forms; pro¬ 
vided with sheaths. Spicules terminate in a rather 
prominent rounded enlargement (fig. 17). The 
sucker is circular, variable in size, measuring from 
0.2 to 0.25 mm. in adult specimens; considerably 
smaller in immature forms. The length of the tail, 
which ends in a slender tip in adult forms, is from 
0.5 to 0.7 mm. 
Fig. 17.—Tip of spicule of Ascaridia lineata viewed 
from different aspects (original) 
Female. —The vulva lies approximately at the 
middle of the body. Eggs thick-shelled, elliptical 
in shape, 80 ^ long by 50 n wide. Anus from 1.1 to 
1.3 mm. from tip to tail in adult forms and shorter 
in immature forms. Tail ends in a slender tip 
(fig. 18). 
Hosts. —Gallus domesticus, Anas boschas domes - 
ticus, and Anser domesticus. 
Localities. —Europe, North and South America, 
Asia, and Africa. 
THE GENUS ASCARIDIA DUJARDIN, 
1845 
Railliet and Henry (11) define the 
genus Ascaridia as follows: Mouth 
with three lips; esophagus without a 
bulb, often with lateral membranes. 
Caudal alae of male feebly developed. 
Spicules equal or subequal, without 
an accessory piece. Preanal sucker 
rounded, with chitinous ring; papillae 
relatively large. Vulva toward the 
middle papillae of the body; uteri 
opposed; eggs thick-shelled. 
In a paper on suckered roundworms, 
Lane (5) amends the diagnosis of the 
genus Ascaridia as given by Railliet 
and Henry, by adding the following 
generic characters: 10 pairs of caudal 
papillae in the male, and similar spic¬ 
ules. In a later paper Lane (6) dis¬ 
cusses the generic diagnosis of Ascari¬ 
dia in greater detail, insisting on the 
view that species having more than 
10 pairs of papillae that are now 
assigned to the genus Ascaridia should 
be placed in another genus, but he 
makes no further reference to similar¬ 
ity in size of spicules. According to 
Travassos (16), the male of Ascaridia 
columbae has 14 pairs of papillae; 
that of A. truncata, the type species 
of the genus, 15 pairs, and that of 
A. magalhaesi 12 pairs. In addition 
