554 



BULLETIN 100, UNITED STATES NATIONAL MUSEUM 



1905. Idmonea canariensis Waters, Notes on some Recent Bryozoa in 

 D'Orbigny's collection, Annals and Magazine of Natural History, 

 ser. 7, vol. 15, p. 13. ("Fragments of what Smitt described as Crisina 

 hochstetteriana Stoliczka.") 



History. — Idmonea hochstetteriana Smitt, 1872, is not at all the 

 species of Stoliczka, 1864; Waters in 1884 noted this and MacGillivray, 

 1895, confirmed it. It does not belong even to the same genus. We 

 might therefore adopt Smitt's specific name but, in order to avoid all 

 confusion in synonymy, we prefer to employ D'Orbigny's name even 

 though the French paleontologist did not figure his species. 



Structure. — The colonies are very delicate, quite elegant and of a 

 beautiful clear violet color. They must be quite large and fragile 



Fig. 222. — Crisina canariensis D'Orbigny, 1851 



A. Longitudinal thin section X25, made a little in front of the median plane to 

 show the orifice of the tubes. The vacuoles are visible. B. Portion of longi- 

 tudinal section X25, showing the great thickness of the frontal and dorsal 

 epitheca. C. Longitudinal section X25 of an ovicelled specimen showing the 

 long capillary tubes of the dorsal. D. Transverse section, X25, between two 

 peristomes. 



for among our numerous specimens we have discovered only two bases. 

 The one which we figure is quite unusual as it is formed of 4 branches 

 united to a small fragment of bryozoan. Another base fixed to a 

 fragment of alga is likewise composed of many tubulose stems formed 

 by an epitheca with vacuoles. 



This is the first time in our long experience with bryozoa that we 

 have discovered a base of this character. Only one time also have we 

 found a little column of support which proved that the colony is not 

 always perfectly erect. 



