104 THE VOYAGE OF H.M.S. CHALLENGER. 



case, none of the long thorns characteristic of Biddulphia aurita occur. The valves are 

 hirsute, convex, and ornamented with quadrately disposed punctations, while the angles 

 are of conical form. 



The series, which is formed by the direct union of the frustules, was collected in the 

 Sea of Japan. 



Biddulphia japonica, n. sp. (Plate XXIII. fig. 14.) 



Forma parva ; valvis convexis, areolato-punctulatis ; apicibus productis acutiusculis, 

 ad basim inflatis ; cingulo cylindrico punctulato. In mari Japonico. 



This frustule, from the Sea of Japan, is not mucb larger than those of Biddulphia 

 pumila, n. sp., from which, however, it is at once distinguishable by its areolate ornamen- 

 tation, and by the fact that the angles which are equally prominent are not simply 

 conical, but present a protuberance near the base. The cylindrical cingulum is punctated. 



Biddulphia, sp. (?) (Plate XXVI. fig. 1.) 



The valve here shown is from the Arafura Sea. It possesses an elliptico-lanceolate 

 form, with rounded, somewhat mammiform vertices, while the surface has distinct granules 

 which radiate from a very excentric point. Near the extremities there are two small 

 pseudo-openings. Although this valve cannot be identified with any species hitherto 

 recorded, it does not afford the means of fully determining the characters of the new 

 species which it represents. 



Biddulphia, sp. (?) (Plate XXIII. fig. 13.) 



This organism, like the one last mentioned, cannot be identified with any known 

 species, and is insufficient to enable a complete conception of the new species, which it 

 typifies, to be obtained. It is of elliptical form, and its punctations radiate from the 

 centre, at which a small group of more salient granules or denticules occur. 



Biddulphia weissflogii, Grim. (Plate XXVI. fig. 2.) 



Forma subquadrata, decussatim punctulata ; apicibus parum productis linea axiali vix 

 perspicua unitis ; valvis ellipticis, ad centrum subinflatis, duplici brevi cornu excentrico 

 ad apices instructis. 



This perfect frustule is adorned with very minute granules, disposed in a quincuncial 

 manner. Its extremities are slightly prolonged and rounded, and, when seen from the 

 zonal aspect, each presents two short strong conical and slightly curved points, which are 

 quite characteristic of the species. 



In Plate c. figs. 1 and 2, of the Synopsis des Diatomees de Belgique, by Dr H. van 

 Heurck, there is represented a frustule which is identical in its principal characteristics 

 with that brought home by the Challenger which is now being considered. It has been 



