PROCEEDINGS OF TEE NATIONAL MUSEUM. 191 



C. pectinata that the question forces itself upon us whether these dif- 

 ferences can not be considered as subspeciiic, possibly due to some 

 extent to a difference of conditions found in different hosts iind in 

 different countries. I franlcly admit that during an examination of a 

 large series of specimens 1 have changed my mind a dozen times in 

 regard to tliis particular species, I am now of the decided oi)iiiion, 

 however, that this form should be given specific rank. 



The specimens upon which this description is b;ised were collected 

 at Bowie, Maryland, by Elassall from the cottontail {Lcpus si/lraficKs). 

 The strobila attains 100 to 180 mm. in length and !(► mm. in breadth. 



The head is very small, measuring 0,o2 to O.oO mm. broad; it may or 

 may not be shai ply defined from the neck ; no rosteilum or hooks visible; 

 the suckers are small, measuring O.lL* to 0.2S mm. long by O.llli to 0.1*4 

 mm. broad; the opening of the sucker is directed diagonally forward. 

 The neck is veiy short or absent, se.iimentation beginning very early and 

 the proglottids rai)idly becoming distinct. The anterior portion varies 

 greatly in shai)e, according to contraction. The genital anlagen appear 

 rather early; at about 5 to 10 mm. from the head two roundish bodies 

 appear in each segment, one on each side of the median field near the 

 longtudinal canals; these anlagen soon change in form to the ])istol- 

 shaped anlagen described for Momezki; at about 25 mm. from the 

 head the first testicles are visible. The genital pores are double and 

 opi>osite, and situated in about the middle third of the inargin. 



Segments Vl~> mm. from the head measure O.^G mm. long by 0,5 nmi. 

 broad by (KiS mm. thick. Male organs: The testicles number about Go 

 to 90; they are confined to the dorsal halt of the segment distally of 

 the transverse uterus, and do not exten'd laterally of the ovaries. The 

 cirrus pouch lies dorsally of the vagina on both sides of the segment; 

 It is long, narrow, and quite indistinct, coloring in carmine much more 

 lightly than the vagina. Female organs: The vagina runs veiitrally 

 of the cirrus; it is long and narrow. From the margin of the segment 

 for a distance of about 0.48 mm. it is surrounded by a deeply coloring 

 layer of cells, and then it is reduced to a thin narrow canal which later 

 swells into the receptaculum seminis. The ovary, shell gland, and 

 vitellogene gland resemble those of Moniezia and C. j)ecti)i<;ta and lie 

 1.28 mm. from the lateral margin. The uterus may be double or single; 

 in some segments a single uterine anlage extends across the entire seg 

 ment, running through the ventral portion of the ovary, and j)assing 

 to the lateral rields dorsally of the longitiulinal canals and nerves; in 

 the majority of segments there are two distinct uterine anlagen, one 

 to each set of female glands. The venti'al canal runs about midway 

 between the ovary and the lateral margin; the dorsal canal lies dorso- 

 median of the ventral canal and is bound by a heavy cuticular lining. 

 The longitudinal nerve lies laterally of the ventral canal, and ventrally 

 of the genital ducts, about 0.(>4 mm, from the lateral margin. 



In the older segments the topogiaphy described above is preserved, 



