276 Mr. H. J. Carter on 



and illustrated by Merejkowsky under the name of '^If. 

 ScJmhir' (Mem. Acad. Sc. St. Petersb. 1878, tome xxvi. 

 no. 7, pi. i. figs. 1-6, and pi. ii. figs. 9-15) appears to me to 

 be no other than Halisarca Dujardim, which is as abundant 

 on the rocks and Fuci at Budleigh-Salterton (S. Devon) at 

 " half-tides " as in the " White Sea.'' 



In 1874 I gathered some branches of the small Fuci here 

 bearing specimens of this sponge, and put them at once, that 

 is on the spot, into some sea-water containing iadigo paint in 

 solution, in order to see if the sponges took in the latter, 

 which was the case ; so I placed the whole in spirit for 

 preservation. Now (in 1886), finding that JMerejkowsky had 

 discovered certain ''glands" in his species {I. c. p. 32, pi. ii. 

 fig. 9 5), and conceiving that it was the same as H: Dujardini^ 

 I gently raised one of the specimens (about 1-1 2th in. in 

 diameter) from the frond of the Fucus to which I have 

 alluded, and placing it in a microscope -cell filled with glyce- 

 rine^ brought it under a magnify ing-power of about 300 

 diameters, v/hen, to my great delight, I saw the cells which 

 Merejkowsky had described and represented, particularly as 

 he has stated, viz. about the " osculum " (p. 33), which, pro- 

 jecting from one side of the object, is in a very favourable 

 position for observations of this kind, that is by transmitted 

 light. Moreover, as the spongozoa had become coloured by 

 the indigo, while not a particle was to be seen in these bodies, 

 termed by Merejkowsky " glands," it is evident that the 

 latter at least are not for nutrient purposes. 



After this I stripped ofif a bit of the dermis from one of 

 Mr. Wilson's specimens of Halisarca australie7isis, and 

 having stained it with blue ink, also mounted this in a " cell " 

 with glycerine^ when a similar layer of bodies became equally 

 evident, mutatis mutandis of course, that is with more strongly 

 marked fibrous structure than in H. Dujardini, so that the 

 difference between the two was rather quantitative than quali- 

 tative, as before explained. 



Similar bodies in his Dendrilla rosea &c., from the south 

 coast of Australia, were described and represented by Dr. v. 

 Lendenfeld in 1883 (Zeitschrift f. wiss. Zoologie, Bd. xxxviii. 

 p. 278, pi. xii. fig. 2ld), and by Dr. Pol^jaefF in 1884 

 (' Challenger ' Reports, vol. xi. pt. xxxi. Keeatozoa, p. 40, 

 pi. ii. fig. 5), in lanthella, &c. So that the existence of these 

 organs is well established and probably their function, that 

 which Merejkowsky originally assigned to them, viz. " uni- 

 cellular glands," which secrete the " viscous " matter of the 

 surface [1. c. p. 34). 



