1906.] ON MAMMALS FROM BECHUANALAND. 101 



(Verrill, 7) resembles Corymorpha in its possession of root-like 

 fixing-processes at the base. 



From all these genera of the Pennaridse [sensic stricto), however, 

 Trichorhiza is separated by the characters of its hydrorhiza, aiid 

 also by the possession of a sort of theca, comparable to that of a 

 calyptoblast. The branches of the hydrorhiza may be compared 

 with the filamentous processes of the base in Corymorpha, but 

 there is no real affinity between the two structures. 



The medusoid of Trichorhiza, so far as one can judge from an 

 immature specimen, resembles the medusoid of Pennaria tiarella, 

 which, however, has no developed tentacles at all (Ayres, 2), while 

 the medusoid of Trichorhiza seems to have one tentacle-bulb more 

 developed than the other three, and in this respect approaches to 

 the medusoids of the Corymorpha-\\k.Q foimas, most of which bear 

 one developed tentacle. 



On the whole, Trichorhiza is to be associated with the Pennaria- 

 like forms, though the characters of its hydrorhiza and its "theca" 

 give it a somewhat isolated position among them. 



References. 



(1). Allman, G. J. — Monog. Gymnobl. Hydroids, vol. ii. (1872). 

 (3). Ayres, W. 0.— Proc. Boston Soc. Nat. Hist. vol. iv. (1852). 

 (3). Delage et Herouard. — Traite de Zoologie Concrete, tome 



ii. pt. 2 (1900). 

 (4). Fowler, G. Herbert. — In ' A Treatise on Zoology ' 



(Lankester), vol. ii. (1900). 

 (5). MoTZ-KossowsKA, S. — Archives de Zool. exper. et gen. 



ser. iv. tome iii. (1905) p. 39. 

 (6). Schneider, K. C— Zool. Jahrb. x. [Syst.] (1898) p. 472. 

 (7). Yerrill, a. — Amer. Journ. Sci. (3) xvi. (1878) p. 374. 



EXPLANATION OF PLATE V. 



Fig. 1. Trichorhiza brnnnea. Hj'dvoid, p. 99. 

 Fig. 2. Trichorhiza bi-unnea. Medusoid, p. 100. 



5. A List of the Mammals obtained by Messrs. R. B. 

 Woosnam and R. E. Dent in Bechuanaland. B)- 

 Harold Schwann, F.Z.S. 



[Received December 15, 1905.] 



(Plate VI.*) 



This very interesting collection, made by Messrs. R. B. Woosnam 

 and R. E. Dent in Bechuanaland, was obtained chiefly at two 

 localities, viz. Kuruman and Molopo. The former is situated 

 about 100 miles south-west of Vryburg on the Kuruman River, 

 whose course flows parallel to the range of hills bearing the same 



* For explanation of the Flate, sec p. 111. 



