126 Proceedings of the Royal Irish Academy. 



(iv) ':' histology. — The ectoderm, as far as the portions which I 



sectionized are concerned., seems to have almost entirely vanished, so that 1 

 can say nothing about it. The mesenterial filaments have well-developed 

 ciliated lobes, which, in a simple trefoil, are similar in size and shape to the 



i lular lobe, and when large are folded. The glandular lobes contain a fair 

 Dumber of narrow, medium-sized, blunt-ended, thick-walled cnidae, and a few 

 _ aular gland cells. 



(v) ' sei is distinguished from other species in the genus by 



the curiously thicken- to the tentacles, and also by differences in its 



sphincter and met -radial-musculature, for the details of which 



reference should be made to the descriptions of several species given by other 

 authors. 1 30 and 57. 



1 have named it aftei P. II. because, as far as 1 am aware, no 



Actinian bears the name of the well-known zoologist whose "Actinologia 

 Britannica" was really the foundation of the serious study of Actiniaria. 



Stomphia (losse. 



" with body-wall of varying thickness, devoid of vermcae, 

 collar, ri I and sphincter simple. Numerous perfect 



mesenteries with diffuse pennons. Longitudinal muscle- of tentacles meso- 

 M re than iv. i tentai 



10. S. churchiae < I 



L.R10. May 3, 1905. Nymphe bank. 41-42 fathoms 1." miles oil 

 Mine He. id. 1 specimen. 



3R L358. May 6, L912. 12 miles S. by W. \ \V. of Chicken Rock 

 ; :t. Lit. N ' 50'; !. tg."W I 51' D _ . 15 fathoms, ^specimens 

 Carlgren has already fully described i single specimen of this species (6), 

 I will merely note one or two points with regard to the live further speci- 

 mens in this collection. The mesogloeal sphincter agrees well with Carlgren's 

 figures (Taf. IX. figs. 2 and 3j ; the mesenteries also agree essentially, though 

 in my specimen the mi contains rather less mesogloea, and the 



pn nnon are proportionately higher — probably a merely 



individual variation. 



One of my speci - the tentacles 16 + 17 + 33; another has them 



16 _ third. 13 - 15 + 31 (here two primary tentacles are absent, 



if not three, and the whole of that sector of the disc is aborted; ; the fourth, 

 16 +■ 15 (on. radius present ; two of the primary 16 aborted 



+ 32 ; and the fifth 1 5 ■ 1 . From this it would seem that an octamerous 



plan— 1 2— is typical of the species, though not always carried out 



