The Asiatic Tapeworm — DAVAINEA ASIATICA « (Linstow, igoi). 
[Figs. 109 to 113.] 
Specific diagnosis. — Davainea (p. 62): Length 29.8 
cm., maximum breadth 1.276 mm., composed of about 
750 segments. Head unknown. Segments all broader 
than long, varying in size from the anterior to the ter- 
minal as follows: 0.16 mm.; 0.67 by 0.32 mm.; 1.056 by 
0.352 mm.; 1.276 by 0.88 mm. ; 1.78 by 0.99 mm.; thick- 
ness, 0.238 in middle segments to 0.484 mm. in terminal 
segments; the distal margin of each segment extends 
over the proximal margin of the next following seg- 
ment. Cortical layer | of dorso-ventral diameter of seg- 
ment. Ventral canals very large, § of dorso-ventral and 
| to j of lateral diameter of segment, connected distall y 
in each segment by transverse canal 88 /t in diameter; 
dorsal canals much smaller, T X T of dorso-ventral and ||j 
of transverse diameter of segment, situated dorso-me- 
dian of ventral canals. Lateral nerve about half-way 
between ventral canal and lateral margin. Calcareous 
corpuscles absent. Maturity of segments attained about 
35 mm. from anterior end of strobila. Genital pores 
unilateral in proximal third of margin. Male organs: 
Testicles, 35 to 44 ja in diameter, 14 or 15 on each trans- 
verse section, arranged in single dorsal and ventral 
rows; vas deferens extends in convolutions about | 
across the segment, dorsally of longitudinal canals and 
nerves; cirrus pouch pyriform, 79 ju long by 49 u broad, 
does not quite reach the longitudinal nerve. Female 
organs: Ovary extends across the segment, from vent- 
ral canal to ventral canal; vitellogene gland nearly 
globular, median, dorsal of ovary, its transverse diam- 
eter about } of the segment; vulva dorsal of cirrus; 
vagina extends dorsally of nerve and lateral canals, and 
at dorsal canal it widens into large, elongate, receptacu- 
lum seminis; uterus breaks up into 60 to 70 egg balls in 
each segment; mature eggs not observed, but probably 
about 38.6 by 36.4 ju. 
Habitat. — Adult in intestine of man. Larval stage 
unknown, probably in some invertebrate. 
Geographic distribution. — Known only for Aschabad, 
Asiatic Russia. 
Medical significance. — U nknown. 
Prevention. — U nknown . 
asiatica. Natural size. (After 
Linstow, 1901, 983, fig. 1.) 
« Synonym . — Tsenia [ Davainea ] asiatica, Linstow, 1901. 
14632— No. 25—06 5 
