Greville^ on Aster olampva. 
115 
one more ray tlian its predecessor. In every other respect 
they are precisely similar. 
7. Asterolampra Dallasiana, n. sp.^ Grev. — Areolated seg- 
ments square at the base ; umbilical lines straight ; median 
lines campanulate. Diameter -0038". (PL lY, fig. 10.) 
Hab.—liL Bermuda Tripoli/^ Mr. E. W. Dallas. 
The diatomist cannot fail to observe how similar this form 
is to some of the species described in the first section^ with 
the exception only of the median ray and median lines. In 
general habit it is widely different from all the Asteromphali 
of Ehrenberg, but agrees more with the following species_, 
also detected by my lynx-eyed friend, Mr. Dallas, in the 
same material. The precise locality of this famous Tripoli" 
was for some time a mystery ; but the readers of the ^ Micro- 
scopical JournaF will be aware that Professor Walker- Arnott 
believes that he has traced it to a place called Bermuda, 
about twenty miles below Richmond in Yirginia."^ Con- 
sidering that the genera Heliopelta, Cr asp e do discus, &c._, have 
never been found elsewhere, it may be said to be the most 
precious deposit known ; and the discovery in it of two new 
species of the present section of Asterolampra will add not 
a little to its interest. It is remarkable, however, that if it 
really forms a part of the great Bichmond deposit, nothing 
like it should have been found since the original supply 
passed into circulation. 
8. Asterolampra Wallichiana, n. sp., Grev. — Areolated seg- 
ments square at the base ; umbilical lines straight, the two 
median one scuneate. Diameter "0021". (PL IV, fig. 11.) 
Hab,—ln " Bermuda Tripoli," Mr. E. W. Dallas. 
Only one specimen of this species has been seen, and it is 
conspicuous for the polygonal aspect of the hyaline area, 
which resembles the disc of an Ophiura. There are only six 
rays, and the basal portion of each is so wide next the areo- 
lated segments, that it may be compared to a short-bladed 
trowel, while the linear part represents the handle. These 
relative proportions, however, may not be constant. 
9. Asterolampra Beaamontii. — Areolated segments curved 
at the base ; umbilical lines with an angular bend ; median 
lines straight, parallel. 
Astei'omplialus Beaumontii, Elir., Berl. Monatsb., 1814, p. 200, pi. 
(June), fi^^, 5 ; Kiitz., 1. c, p. 130; Pritcli., I. c, p. 321; Mic. 
Diet., p. 71, 2d edit., Pi. 43, fig. 15. 
Hab. — Antarctic Ocean, Dr. J. D. Hooker. 
* 'Mic. Jouni.,' vol. vii, p. 254. 
