NOVARA DIATOMS. 93 



This appears to be a very constant species, it bears the most 

 resemblance to A. Malleus, Wallicb, but differs in many respects 

 from that species. A peculiar characteristic of our species are the 

 short rays on the inferior punctate portion of the valve, and the 

 two broad rays reaching the superior margin. All examples we 

 have observed are very constant in form. 



Stictodiscus californicus. Orev. Var. nankoorensis. Chun. — 



Costa 1 radiant, generally bifid as they approach the margin, irre- 

 gularly reticulate in the centre. 



PI. 6, fig. 8, a. b. part of a larger valve. Polycystin stone. 

 Nankoori. Somewhat rare. 



As in Dr. Greville's species a row of large granules lies between 

 thecostaj; the costa> divide as they approach the margin, so that 

 more rows of puncta will be found near the circumference than near 

 the centre. The irregularly disposed puncta of the middle portion 

 are placed in a kind of network, from which apparently the mar- 

 ginal costa: proceed ; this may also be seen in the Californian 

 species. 



Climacodium Fraunfeldianum. Grun. — Frustules scarcely 

 silicious, smooth, expanded at the ends, truncate, forming long 

 filaments. PI. 6, fig. 10. 



In the sea by Tilanshong, floating in masses. 



A wholly distinct genus, with very weak siliceous frustules, 

 which perhaps remotely approach Eucampia Zodiacus, one of the 

 specimens consisted of 16 frustules, the frustules were -007 long. 

 I know no form that can be better compared with a little ladder 

 than this. I have therefore given it the above generic name. 



(This form appears to be a very doubtful diatom. The author 

 gives no side view, and the figure shows no connecting zone be- 

 tween the valves ; it approaches more closely to Triceratium 

 malleus, Brightwell, which is also a very doubtful diatom. (F. K.) 



Plagiogramma spectabile. Grev. Var. quadrigibbum. Grun.— 

 Valve lanceolate, constricted at the centre, and with two smaller 

 constrictions between the ends and the central constriction, apices 

 produced acute, central nodules, elliptical in a transverse smooth. 

 central fascia, median line absent ; puncta minute (30 to 32 in. 

 •001 in longitudinal and transverse lines). Costas pervious. PI. 

 6, fig. 7. 



In Polycystin stone. Nankoori. 



Differs chiefly from Greville's species in the greater number of its 

 undulations, and the smaller number of its stria 5 , which towards the 

 end are closer, whilst in Greville's figure they are equally distributed 

 over the whole valve. 



Cocconeis surirellcides. Gnm >- Minnte, valve broadly ellip- 

 tical ; upper valve median line narrow, straight, centra] nodule 

 obsolete, costae subradiant, 20 in. -001 furrow elliptical, submar- 

 ginal interstices granulate. PI. 6, fig. 11. 



