1899] WELWITSCH'S COLLECTION 355 



Welwitsch, his eminence as a careful and scientific collector and the 

 great value of his collections, in the possession of which the British 

 Museum may well feel proud. It is also matter for congratulation to 

 all concerned that the parts of the catalogue follow each other at such 

 short intervals, thus giving the promise of a speedy completion of the 

 work. 



American Mammalogy. 



The first twenty-five pages of the January issue of the Proc. Biol. Soc. 

 Washington (vol. xiii.) are occupied by papers on mammals from the 

 pens of Messrs. Bangs, Merriam, Miller, and Palmer. Most of the 

 matter in these communications is devoted to the never-ceasing de- 

 scriptions of new species and sub-species, and the usual edifying contro- 

 versies and arguments on nomenclatural questions. Mr. Miller's 

 paper on the naked-tailed armadillos, for which the name Tatoua is 

 stated to be the proper title, is, however, of more than ordiuary interest ; 

 and perhaps some of our readers may like to know that such a familiar 

 name as Orca, for the killer -whale, has, according to the strictest 

 rules of nomenclature, no right to stand. 



Flame Cells in Rotifera. 



Mr. J. Siiephakd has written an interesting note on the structure of the 

 vibratile tags or flame cells in Eotifera in the Proceedings of the Royal 

 Society of Victoria, vol. xi. (N.S. pt. ii. p. 130). He describes the 

 tag as a flattened funnel, closed at one end by a protoplasmic mass, to 

 which is attached an undulating membrane, lying within the funnel, 

 and two fiagella as first seen by Eousselet (or one), playing freely 

 outside in the coeloni. He regards the appearance of the bundle or 

 row of long cilia as due to a combination of the effect of the undulating 

 membrane and the structure of the side walls of the funnel, which he 

 describes as a striated membrane. Moxon, in 1864, noted the 

 appearance of rows of waves passing along these side walls, and the 

 appearance is familiar. Mr. Shephard notes, in addition, that by careful 

 focussing a face view two such wave rows can be seen, one above the 

 other ; and this is his only evidence for the " striated " membranous 

 wall. There is no necessity for this assumption. For if a row of 

 cilia or undulating membrane vibrate, its face view will appear as a 

 set of waves at the "loops " where it most closely approaches the wall, 

 while the intermediate parts will be less visible ; and if the optic 

 angle of the lens be high enough to give a sufficiently thin optic 

 section, the loops at the one side will come into view at a different 



