1 88 TAPEWORMS OF HARES AXD L'A Uni TS—STILES. 



I can add a IVw ])()iiits of importance to Kiehin\s diagnosis and lay 

 greater stress npon other points wiiicli I think shonld be brought oui 

 more empliatically. 



The anhigen of the female glands and genital canals appear in the 

 earliest si'ginents, while the testicles begin about 7 n)m. back of the 

 head. j\Iale organs: The testicles are confined entirely lo that portion 

 of the segment wiiich lies distally of the uterus, and they extend on 

 both sides laterally of the ovaries to the longitudinal canals; this latter 

 character is one of considerable imjxtrt a nee wlieii \vccomi)ar(' the Anieri 

 can and the Euroi)ean forms. IJichm has already directed attention to 

 the loughoselike cirrus pouch and vagina, but I venture to call i»articu 

 lar notice to their size and form. 



Female organs: The excessive development which the female glands 

 may attain is worthy of note: lliehm's statement that each ovary 

 was divided into two halves I was unable to contirm. A peculiar 

 feature of the female glands is that they develop suddenly and atrophy 

 suddenly. In Riehm's cotype, for instance, the tubes of the ovary be- 

 come visil)le 8 mm. from the anterior end (head lost) ; they then develop 

 rapidly to a maxinnim and suddenly disappear, so that 22 mm. from the 

 point where the ovarian tubes appear (or about 30 mm. from the anterior 

 extremity) the ovary can no longer be seen; the testicles persist vQvy 

 much longer. The lirst trace of the uterus is seeu about 12 mm, from the 

 anterior end of sitecimen (about 14 mm. from anterior end of individnjil. if 

 we allow 2 mm. for the lost head and first segments); the uterus passes 

 on the ventral side of the ovary, and in all segments which 1 have exani- 

 iued there is a single uterine aulage extending across the segment. 



The genital canals and uterus run dorsally of the nerve and ventral 

 canal as Kiehm figures them, and on transverse sections the ciirus is 

 shown to lie dorsally of the vagina on both sides of the segment. The 

 nerve is very close to the lateral margin. 



Kiehm gives no measurements for the ova; Blanchard (18!H. p. 4G0) 

 states that the ova measure M) to 00 // by 7.") //, and that the bulb of 

 the pyriform body measures 25 to 30 /.i in diameter. The measurements 

 in Riehm's specimen are somewhat smaller, the ova varying from 72 to 

 84 //, the bulb of the pyriform bod}' 14 to 16 /t. ^ly own specimens 

 agree with Riehm's, but manj' of the ova do not exceed oG // in 

 diameter. 



The following is i)roposed as a revised specific diagnosis: 



])i<i[/n(>si.s. — Cittotienia pcctinula ((xoeze, 1782, partim, Riehm, 1881), 

 Stiles & llassall, 1806. Strobila may attain 400 mm. in length and 8 

 mm, in breadth, anterior portion usually lanceolate. Head snndl, about 

 0.25 mm, or less in diameter, and about 0,125 mm, thick; rostellu.n and 

 hooks not observed; suckers snuill. ISTeck very short, segmentation 

 beginning almost immediately back of the head ; the proglottids rai)idly 

 become distiiu't and are always nuich broiuler than long, the length being 

 about one-seventh of the breadth: gravid [(osterior segments measure 



