REPTILIAN TAPEWORMS. "33 



pores is as great as that of the diverticula. But I cannot reckon 

 these pores up exactly. The actual pore itself is as a rule small, 

 but its position is rendered obvious by the gradual thinning to a 

 point of the cuticular layer on either side. Where the pore is 

 small the downwardly directed tube from the median stem of 

 the uterus is also slender and narrow. 



JSTot infrequently, however, the pores are greatly enlarged, and 

 in such cases I have observed the orifice plugged with granular 

 matter exuding from the orifice. Very often too, and in association 

 with the stretching of the uterine pores, the ventrally directed 

 outgrowths of the uterus are much dilated. It might be suspected 

 perhaps that these large " pores " are simply the expres.-^ion of a 

 rupture caused by the turgescence of the uterus. That this is 

 not the case is shown by the thinning of the chitinous cuticle 

 round the pore ; it is clearly not torn across, as it would be were 

 it a question of a rupture. 



If there were any doubt as to this tube with its paired 

 diverticula being the utei'us, the existence of eggs within the tube 

 dissipates that doubt. These possess a tolerably thick shell and 

 they appear to resemble the eggs of Ichthyotcenia varia. But in 

 addition to these eggs (which had segmented and were of course 

 really embryos) there were others with no apparent shell (text- 

 fig. 9, d). Attention has been called to the diverticula of the 

 uterus, which are small and whose walls are beset with numerous 

 long-stalked pear-shaped glandular cells. If it were not for the 

 comparatively wide lumen of these diverticula they might easily 

 be mistaken for shell-glands — so similar is their glandular invest- 

 ment to that of a shell-gland. I am disposed, indeed, to believe 

 that this is the actual function of the diverticula. For there are 

 to be noted here and there in the uterus round homogeneous 

 masses of a substance (text-fig. 9 A a?, C d) which stains precisely 

 like the egg-shell, and which may veiy well be a secretion of the 

 glandular cells referred to. It will be furthermore recollected 

 that this worm apparently does not possess a proper shell- 

 gland*. 



The function of the uterus is thus enlarged, and it is in this 

 species not merely an egg-holder. 



* It seems to me to be possible that an iiiialog-ous state of affairs exists in 

 Mesooestoides. I have lateli^ spent some time in studying a ispeuies of that genus 

 from a black Serval, which I do not feel able to place accuratelj' but have regarded 

 as M. litterata. In the uterus masses of amorphous matter lie here and there among 

 the embryos. This substance is represented by Hamanu (Zeitschr. f. wiss. Zool. 

 1885) as a nucleated tissue, with which I cannot agree. I think that we have to do 

 here, as in the species described above, with a secretion of uterine glands. The 

 hinder part of the uterus is regarded by Haniann as the equivalent for shell-gland 

 which he has stated to be absent in Mesooestoides. Zschol<ke, however (M^m. Inst. 

 Geneve, 1889), has asserted the presence of a real shell-gland in the normal position. 

 If a shell-gland is present in the species which I studied it is certainly very incon- 

 spicuous. 1 may point out, moreover, that in the genus with which the present 

 paper deals the shell-gland may be present or absent. In any case, the commence- 

 ment of the uterus in the 3Iesocestoides examined by myself had a glandular wall, 

 which quite possibly corresponds with the glandular diverticula of the uterus in the 

 species from the Indian Cobra. 



Proc. ZooL. Soc— 1913, No. III. 3 



