sphincter (later renamed spliincter and glazing gland). 

 Since, as Looss describes them, the four cells at the uterine 

 end act as a suction funnel, we suggest the name 

 infinidibiiliim for them; and since the second group of 

 cells act as a sphincter, the name is retained. The prox- 

 imal pai't of each ovejector in Ancylostoma consists of 

 four sets of two cells (III-VI) and one set of four cells 

 (VII), making a total of 12 cells; in addition the two 

 vaginal ends of the ovejectors are united with each 

 other and with the vagina by four cells. For the uterine 

 ends of the ovejector Looss' term ejectrix is retained. 

 From the observations by Looss, Maupas and Seurat, 

 and the writers examinations of Oesophagostomiim denta- 

 tiiyn and Kalicephalus sp., we judge cell constancy to be 

 the rule for ovejectors in the Strongylina. The paired 

 ovejectors with the union piece in Ancylostonui include 

 28 cells, the two sphincters and the two infundibula, four 

 each or 16 cells making a total of 44. Seurat lists the 

 ejectors as including 32, the sphincters two each, and 

 the infundibula four each, also making a total of 44. 

 We have found the same total in both nemas studied by 

 us. Diffei'ences in appearance as suggested by Seurat 

 are minor modifications; he found the same cellular ar- 

 rangement in Nematodirus ynauritanicus and N. filicollis 



but tremendous cellular hypertrophy in the ejector oi 

 the latter species. Slight modifications of cellular ar- 

 rang-ement do exist, however, for we found tetraradiate 

 symmetry (Fig. 122 P) throughout the ovejectors of 

 OesophagoMomum while Looss found sets of two cells in 

 the ejectrix of Ancylostoma and Seurat a set of two 

 cells in the sphincters of Nematodirus. 



In no instance have the cells of the vagina vera been 

 identified separately from the ectodermal epithelium. 

 The musculature of the ovejectors is the same as the 

 type which covers the uterus of nemas, that is, circular, 

 oblique, and having spiral anastomosing fibers. When 

 concentrated in a specific area they form a conspicuous 

 sphincter. 



The primary amphidelphic form is preserved chiefly in 

 the families Ancylostomatidae and Trichostrongylidae 

 (Fig. 116 T) in which the vulva tends to be only a short 

 distance postequatorial. In the majority of other families 

 of the suborder Strongylina the vulva is preanal in 

 position. In such cases the paired ovejectors may sepa- 

 rate in an amphidelphic manner before extending an- 

 teriad and thus becoming prodelphic as in Oesophagosto- 

 miim or they may originate in a prodelphic manner as 

 in Kiluluma (Fig. 117 X) and Zoniolaimus (Fig. 117 U). 



121. ASCARIS LVMBRICOIDES SECTIONS. 



A-B — Surface view of uterine epithelial cells. C — Junction of 

 seminal vesicle and uterus. D — Junction of furrowed and smooth 

 regions of oviduct, E — Junction of vagina uterina and vagina vera. 

 F — Cross section of vagina vera. G-L — Cross sections of germinal 

 region of testis. M — Surface view of blind end of testis. N — Surface 



view of epithelium in growth zone of ovary. — Same near end of 

 growth zone ; PS — Cross sections in germinal region of ovary. 

 T — Totomount preparation of terminal region of ovary. U — 

 Longitudinal section through germinal region of ovary. All after 

 Musso, 1930, Ztschr. Wiss. Zool. v. 137 (2). 



147 



