ART. 13. NEW NEMATODES FROM LAND-TOETOISE — CHAPIN. 3 



Vagina 1.5 mm. long, muscular but without muscular ovejector or 

 sphincter. Uteri convergent, soon parallel, extending forward to 

 just in front of the middle of the worm. Ovaries extending between 

 the end of the uteri and the excretory pore. Eggs (in uterus) 

 12SiJLX57i;.. 



Host. — Testndo denticidata {Testudo tabidata). 



Location. — Intestine (large ? ) . 



Locality, — Brazil, Para. 



Type.—\J. S. N. M. Helm. Coll. No. 25446 in glycerine. Para- 

 types (part in glycerine, part in 70 per cent alcohol). Cat. No. 

 •25394 ; also in the British Museum. 



Genus DELETROCEPHALUS Dies. 



DELETROCEPHALUS VARIABILIS, new species. 



Specific characters. — Deletrocephalus ; length ^ up to at least 8 

 mm., form cylindrical, tapering sharply at anterior end, cuticle with 

 widely spaced transverse striae, mouth collar distinct, circumoral 

 papillae six, laterals about 20^1. long, apical half cylindrical and much 

 smaller in diameter than basal half, submedian about 10\i long, 

 simple. Buccal capsule (fig. 6) surrounded by a chitinous ring; 

 10[ji. deep by about 40[x across. Leaf crown single, composed of 

 eighteen slender leaves, each leaf with conspicuous angular bend at 

 about the middle. Esophagus about 370[ji. long, slightly enlarged 

 posteriorly, lumen with three longitudinal rows of chitinous bosses, 

 extending through the anterior three-fourths of the length. Nerve 

 ring just in front of the middle of the esophagus. Excretory pore 

 at or just behind the esophago-intestinal valve. Cervical papillae 

 conspicuous. a])Out one-fourth length of esophagus behind its poste- 

 rior extremit3\ Intestine slender, with a few small caecal dilations 

 towards the posterior end. especially in the female. 



Mah. — Bursa (fig. 7) feebly trilobed, dorsal ray normally divided 

 into three trunks, each of which may, and usually does, bifurcate. 

 Externo-dorsal rays slender, arising about middle of dorsal trunk. 

 Trunk of lateral rays stout, trifurcating at about middle. Postero- 

 lateral and externo-lateral rays stout, medio-lateral more slender 

 and joined at its base with the externo-lateral, tips of medio-lateral 

 and externo-lateral apj^roach one another. Ventrals similar and 

 parallel, their tips approximate. Prebursal papillae absent. Spi- 

 cules (fig. 8) slender, similar, 1.54 mm. long, each with a lateral 

 ala which commences just behind the apex and travels in a long 

 spiral about the spicule, completing three-fourths of one complete 

 circuit. 



* No mature females available for study. 



