52 PEOCEEDI]SrGS OF THE NATIONAL MUSEUM vol. 70 



spines, rather sparsely set, and have a bulbous enlargement near the 

 base (fig. 167), The cirrus-pouch is elongate, cylindrical, its walls 

 largely composed of longitudinal muscles; the inner half, or more, 

 of its length acting as a seminal vesicle. An inner seminal vesicle lies 

 on the dorsal side of the inner end of the cirrus-pouch, which com- 

 municates with the two testes by what appear in my sections to be 

 relatively large vasa efferentia. The vagina, ventral, parallel, and 

 very similar in appearance to the cirrus-pouch, leads to a capacious 

 seminal receptacle. The ovary, vitelline gland, testes, and inner 

 seminal vesicle are massed together along the median line, and are 

 difficult to interpret in whole mounts. The proglottides are very 

 short, their length in some portions of the strobile being less than 

 the axial diameter of ovaries and testes. Thus, in a portion of a 

 strobile where the length of the proglottides was 0.15 mm., the 

 antero-posterior diameter of testes and ovaries was from 0,16 to 0.21. 

 The ovary is lobed, and is ventral to the small, compact vitelline 

 gland. The uterus varies greatly in different parts of the strobile. 

 In earlier proglottides it is more or less lobed; in ripe proglottides 

 it occupies the greater part of the interior. The ova are fusiform 

 (fig. 171). The central excretory vessel is much larger than the 

 dorsal, and has thinner walls. The dorsal and ventral vessel of each 

 pair lie close together, and the genital ducts pass on the dorsal side 

 of the poral pair. 



There are two layers of longitudinal muscles, an outer, consisting 

 of a large number of small bundles, oval-elliptical in transverse sec- 

 tion, and containing a maximum of about six fibers, and an inner, 

 consisting of eight bundles, which are much larger than those in the 

 outer layer. The number of fibers in the inner bundles is variable; 

 as many as 30 were counted in one of them, 



RECORD OF COLLECTIONS 



Marila aniericana, new host : 



1914, February 19. — Four strobiles, two with scoleces; slender, 

 segments indistinct in all but one, filiform, thickish; longest 

 measured 176 mm. ; maximum diameter 1.5 ; breadth of scolcx 

 0.42, of neck 0.37; diameter of rostellum at apex, 0.09. Diam- 

 eter of another scolex 0.27, of rostellum 0.07 ; number of hooks 

 in each 10, length 0.05. 



(U.S.N.M., Helm. Coll. 7887.) 



1914, February 26. — Three strobiles, scoleces missing, slender, 

 filiform, segments indistinct; lengths, 140, 143, 184. 



1914, February 28. — Number not recorded; length of one 30 

 mm., breadth of scolex 0.33 mm. 



