GrevillEj on New Diatoms. 
83 
character. The diameter of the valve varies from '0050'' to 
•0073'^ My friend Mr. Norman^ who was the first to 
examine the Moron deposit, well deserves that this magnifi- 
cent species should bear his name. 
Auliscus Moronensis, n. sp., Grev. — Large ; valve broadly 
oval, with a circular smooth umbilicus ; converging and 
radiating lines beset with numerous minute puncta, the 
lateral ones widely plumose, dichotomous ; processes 2. 
(Fig. 6.) 
Hab. Moron deposit ; George Norman, Esq. ; E. K. G. 
This fine diatom is evidently allied to Auliscus pruinosus 
of Bailey, from which, indeed, it is not easy to separate it in 
words, although it is abundantly distinct. The essential 
difference lies mainly in the radiating lines. These, in 
A. pruinosus, are very fine and delicately scabrous, the latter 
effect being produced by the minute jaggedness of the lines 
themselves. In our new species the lines are far more 
robust, less exquisitely symmetrical, and the apparent rough- 
ness is caused by minute, distinct puncta occurring on their 
surface at short irregular intervals. A. pruinosus is supposed 
to be always circular, but I do not venture to place much 
confidence on that character. Nevertheless it is worthy of 
remark that all the examples of A. Moronensis which have 
come under my observation are broadly oval. Long diameter 
about -0055^" 
BiDDULPHIA. 
Biddulphia punctata, n. sp., Grev. — Side view elliptical- 
oval, the ends sub-obtuse, with short, obtuse, roundish pro- 
cesses and two transverse blank lines; structure uniform, 
composed of minute puncta. (Fig. 10.) 
Hab. Barbadoes deposit, Cambridge estate; C. Johnson, 
Esq. ; R. K. G. 
Of this species I have met with four or five examples, all 
agreeing so closely that I feel justified in regarding it as 
well-defined. The transverse lines do not appear to indicate 
any septum, but they are very conspicuous. The position 
they occupy towards each end of the valve is at about a 
third of its entire length. The short processes very much 
resemble those of B, pulchella. Longest diameter about 
•0055^ 
