Manchester Memoirs, Vol. Ixii. (19 17), No. 4 13 



Anthoptilum grandiflorum, Verril. 



The filaments are slightly sinuous and average 0.045 m.m. in 

 breadth. 



A. Kukenthali, Hickson. 



In a specimen of this species from the Indian Ocean, Mrs. 

 Musgrave (1909 p. 464) observed siphonozooids in the lower part 

 of the stalk. Though small in size they had the usual structure of 

 siphonozooids but differed from others of the colony in possessing 

 no mesenteric filaments. It is interesting to compare this condition 

 with that in Umbellula, where there is some evidence of the fila- 

 ments being present in siphonozooids at the base of the stalk. The 

 explanation may lie in the fact that in Anthoptilum a far greater 

 number of large siphonozooids with well developed filaments is 

 present in the colony, and these extend comparatively much nearer 

 the basal bulb than in Umbellula. In Anthoptilum, therefore, the 

 exhalent currents set up by the filaments of the siphonozooids of 

 the rachis are sufficiently strong to discharge water from the stalk, 

 whereas in Umbellula this is not the case, and filaments are necess- 

 ary in the basal stalk zooids. 



A. MALAYENSE, Hickson. 



The filaments are here more slender than in A. grandiflorum 

 but are considerably more coiled, and extend in some zooids to a 

 depth of 0.5 m.m. from the surface of the colony. In examining 

 the siphonozooids in situ this coiled mass of filaments is very 

 striking. 



VlRGULARIA GRACILLIMA, Kolliker. 



In the genus siphonozooids are comparatively few in number. 

 In this species they are situated on the rachis between leaves, and 

 mesenteric, filaments are absent. 



V. Gustaviana, Herklots. 



In this species, which he described as Halisceptrum, Kolliker 

 (1872 p. 168) observes that the corners of the lower free end of the 

 stomodaeum appear almost like mesenteric filaments, but expresses 

 the doubt "doch habe ich mir nicht die Ueberzeugung zu 

 verschaffen vermocht, dass diese Anhange wirklich diese 

 Bedeutung haben. " It would be of interest if the occurence of 

 short mesenteric filaments was definitely established in this species 

 which is rather of a fleshy character and has a large number of 

 siphonozooids. The same author describes fifteen species of 

 Virgularia, and makes the general statement that mesenteric 

 filaments are lacking. For reference, a list of these species is 



