572 
Journal o f Agricultural Research 
Vol. XXX, No. 6 
There is little or no tapering of the 
terminal dorsal branches; near their 
extremities they are cleft to give off, 
exteriorly, delicate finely pointed proc¬ 
esses; they themselves end bluntly. 
The spicules (fig. 4) are 224 to 240 y long 
and 19 to 24 ju wide; they are of simple 
structure. The muscular attachment at 
their proximal end shows plainly as a 
balloonlike expansion. The telamon 
(figs. 5A and B) is very elaborate. 
On the dorsal surface of the genital cone 
it consists of a strongly chitinized U- 
shaped structure, and posterior to this 
two pairs of papilliform bodies in 
the lateral fields, and in the median 
line a process apparently ending in a 
papilla, extending back¬ 
ward between two chiti¬ 
nized basketlike struc¬ 
tures. Masses of granular 
material extend laterally 
on both sides of the cone. 
On the ventral surface 
there is a prominent 
chitinized structure con¬ 
sisting of two large, 
movable, projecting plates. 
Between them on the 
posterior surface is a 
strongly developed rounded 
body. It is directly below this body, be¬ 
tween it and the papilliform process dor¬ 
sal to it, that the spicules protrude. It is 
possible that the large, movable projec¬ 
tions are clasping organs; the papillae 
may be sensory in nature; the basket¬ 
like structures may serve to support and 
guide the spicules, and the granular 
material may act as a cement plug. 
The telamon has 
not been previously 
described for Coop- 
eria; it is evidently 
the most elaborate 
of any of the tela- 
mons studied up to 
this time. Hall 3 first 
described this struc¬ 
ture in Hyostrongy- 
lus rubidus and Orni- 
thostrongylus quadri - 
radiatus. Lane 4 has 
noted its character in 
Necator congolensis 
and Goodey 5 has re¬ 
cently made a de¬ 
tailed study of it in 
Oesophagostomum 
dentatum. It is evi¬ 
dently present in 
cylicostomes of the horse, as figures by 
Kotldn 6 and more recently by Smit 
and Notosoediro 7 clearly show such 
supporting structures, although the 
authors do not call attention to them 
as telamons. It seems quite probable 
that this structure will prove to be 
of value as a definite specific character 
when it is more widely studied. 
Female. —The female is 8 to 9.5 
mm. long by 157 to 257 y in maximum 
diameter just anterior to the vulva. 
Head 38 to 41.5 y wide, narrowing 
down to 30 to 33 y posterior to the cuti- 
cular dilation. Esophagus 378 to 431 y 
in length by 21 y in smallest diame- 
o t mm. 
Fig. 4. — Cooperia bi- 
sonis. Spicules 
Fig. 5.— Cooperia bisonis. Telamon. A, ventral view; B, dorsal view 
ter, increasing to 33 y near the pos¬ 
terior end. The vulva (fig. 6) is situ¬ 
ated 1.9 to 2.4 mm. from the posterior 
3 Hall, M. C. two new genera of nematodes, with a note on a neglected nematode structure . 
Proc. U. S. Nat. Mus. 59: 541-546, illus. 1921. 
* Lane, C. some strongylata. parasitology 15: 348-364. 1923. 
s Goodey, T. the anatomy of oesophagostomum dentatum (Rud.) a nematode parasite of 
THE PIG, WITH OBSERVATIONS ON THE STRUCTURE AND BIOLOGY OF THE FREE-LIVING LARVAL Jour. Hel¬ 
minthology 2: 1-15. 1924. 
® Kotlan, Sandor. adatok a lOvakban £l6skod6 strongylidak ismeretEhez. N6h&ny fij Cylico- 
stomum-faj lovak vastagbelSbol. Allat. Lapok 43 : 71, 85-86, illus. 1920. 
7 Smit, H. J., and Notosoediro, R. nog eenige strongyliden van het paard op Java. Neder¬ 
land. Ind. Bl. Diergeneesk. en Dierenteelt 34 : 62-68, 224-232, 446^155, illus., 1923; 35: 29-36, illus. 1924. 
