244 Dr. S. F. Harmer on 



the important memoir by K. A. Andersson (6), of which he 

 has been unable to find a copy at Cape Town ; and he asks 

 me to do what I can to remedy the omission. I may be 

 permitted, therefore, to add a few notes on his communication. 



The evidence brought forward to show that C. gilchristi 

 does not grow on the muddy ground on wliich it has been 

 obtained by Dr. Gilchrist in considerable quantities is very 

 interesting. It appears that the Cape species probably grows 

 on rocky ground, from which it may be detached and carried 

 by currents to the muddy areas from which it has been 

 trawled. 



Dr. Gilchrist's observation that the zooids are sometimes 

 found in large numbers crawling on the outer surface of the 

 ccencecium agrees with the description of living specimens of 

 C. dodecalophus and C. incequatus (probably = G. hodgsoni, 

 liidewood ; cf. Harmer and liidewood, 9, p. 559) which has 

 been given by Andersson (6, p. 15). 



The notes on the behaviour of the living zooids are a 

 distinct addition to our knowledge of the genus ; and the 

 remarks on the solution of the normal pigments by preserving 

 fluids, and on their redeposition in the tissues of the zooids 

 from the solution, have a distinct bearing on the interpre- 

 tation of the pigments in the preserved material of other 

 species. Some indication that this is the case has already 

 been recorded in the paper by liidewood and mj'self 

 ( 9 , P . 544). 



Dr. Gilchrist thinks that " there is no evidence that the buds 

 ever develop into normal zooids, and they may be individuals 

 specialized for adhesive purposes and ccencecium-building." 

 1 venture to think that this opinion cannot be maintained. 

 The occurrence of almost innumerable individuals in a single 

 colony almost necessarily presupposes that the number of 

 individuals increases by budding; while Dr. Gilchrist's 

 observation that several zooids may occur in the individual 

 ccencecial tubes of C. (Idiothecia) gilchristi indicates, in all 

 probability, that some of the buds have assumed an adult 

 character. 



It is to be hoped that Dr. Gilchrist will be successful in 

 elucidating further the structure and the metamorphosis of 

 the embryos and free larvae which he has observed in the 

 living condition. In his covering letter he states that some 

 of his embryos show traces of five body-cavities. It is in 

 this part of his paper that he has been most handicapped by 

 the want of literature ; and I subjoin one or two notes on 

 what has already been done in investigating the embryonic 

 development. 



Omitting one or two fiagmentary remarks on embryos of 



