PROCEEDINGS OF THE NATIONAL MUSEUM. 



195 



provided with rather a large rostelhim armed with a double crown of 

 about 90 hooks 18 /< long. Suckers round and <|uite large; hooks on 

 suckers not observed. Genital pores unilateral. A single a^g in each 

 egg sac. 



Host. — Man [Homo sapiens). Found in Mayotte, Mauritius, and 

 Bangkok. 



DAVAINEA CONTORTA, Zschokke, 1895. 



(Plate XXII, -fig. 2.) 



1895, Davainea conforta, Zschokke, Ceutralbl. f. Bakter. 11. Parasiteuk., Ft. I, 

 XVII (18-19), pp. 634-645, figs. 1-4. 21 May. 



Diaynosis. — Davainea contorta, Zschokke, 1895. Strobihi attains 40 

 to 80 mm. in length by 0.75 mm. in breadth, and contains 400 to 800 

 segments, all of which are broader than long; margin of strobila ser- 

 rate. Scolex small, prismatic; rostellum large, armed with (? a single 

 row of) numerous minute hooklets; suckers large, armed with 8 to 10 

 rows of minute hooklets. Genital organs dift'erentiate in fortieth to 

 sixtieth segment. Genital pores unilateral, in midtlle of lateral mar- 

 gin. Male organs: Cirrus pouch one-fourth to one third as long as the 

 segment is broad; testicles two, large, in dorsal portion of median field 

 on aporose side of median line. Female organs : Ovary bilobed ; gravid 

 segments tilled with large egg capsules, each with a single egg pos- 

 sessing two shells. 



Host. — Common Indian Pangolin [Manis pentadactyla). Type with 

 Zschokke. 



DAVAINEA RETRACTILIS, Stiles, 1895. 



(Plate XXI, figs. 1-6; Plate XXII, tig. 1.) 



1895, Davainea retractilis, Stiles, Veterinary Magazine, II, June, p. 343. Aug. 28, 1895. 



Of this species, I have seven strobike, collected March 10, 1891, in 

 Nevada, by Dr. Fisher, of the Division of Mammalogy and Ornithology, 

 United States Dei)artment of Agriculture. The original label reads: 

 "Biological Explorations, U. S. Dept. Agr., Death Valley Expedition, 

 Ash Meadows, Nevada, Mch. 10, 1891. A. K. Fisher. Nye Co. Tape- 

 worms from Cottontail, No. 3(32.'' A reference to the specimen in the 

 Division of Mammalogy and Ornithology shows that the host is Lepus 

 arizonce. 



Measttreinentu of Davaiiua irtractilis. 



B. A. I. Ccstodc 



series (No.). 



1168 

 1187 

 1188 

 1189 

 1190 

 1191 

 1192 



Condition. 



Fragment. 

 With head. 

 Fragment. 

 With head ; tyjie. 



Do. 

 Fragment. 

 With head. 



