Oct. 1, 1S67.] 



HARDWICKE'S SCIENCE-GOSSIP. 



229 



232) measured '0027 of an inch, Navicula palpebrals 

 of Brebisson, which is found ou our own coasts and 

 those of France. My measurement is "0020 of an 

 inch (fig. 233). 



Fig. 232, X 5'0. 



Fig. 23.'), X 50«. 



Two species of Grammatophora are also to be 

 found in my washings. One of these is Grammato- 

 phora marina of Lyngbye, which is also common 

 everywhere, and has been honoured with a variety 

 of names. The measurement of the specimen 

 figured (fig. 234) is '0024. The other species is 

 Grammatophora serpentina of Ehrcnberg (fig. 235), 



Fig. 234, X 500. 



Fig. 235, X 500. 



which is not uncommon in sheltered bays. Length 

 '0015 of an inch. 



The finest form in my series is undoubtedly the 

 "Biddulphia pulchella (fig. 236) of Gray, which may 



It? Sail* 





-- - -. ~%k\ 



Fig. 236, X 500. 



be regarded as the " king of the sponge." Albeit it 

 is a British species, and not one of the most rare. 

 My specimen measured '0034 of an inch. 



Less attractive, but interesting, is the variety (3 

 of Navicula Lyra (Ehr.), a species very much given 

 to variation (fig. 237). The length of my specimen 

 is '0053 of an inch. The same genus is also repre- 

 sented by the Navicula uitida of Gregory (fig. 23S), 



Fig. 237, X 375. 



Fig. 233, X 500. 



a form which was found by bim in the Glcnshira 

 sand. (See his communication in Trans. Mia: 

 Soc, vol. iv.) 



Of the genus Cocconeis, the only representative 

 which I have recognized is the Cocconeis major of 

 Gregory (fig. 239). Length '0024 in. 



...-% 



Uncertain forms also occur in my slides, of which 

 one is the species of Navicula (fig. 240), which 



Fig. 240, x 230. 



Fig. 241, X 500. 



measured "0020 of an inch, and what appears to be 

 the side view of Denticula nana (fig. 241) which 

 measured '0012 in. 



Hence it will be observed that I have detected 

 sixteen forms of marine diatoms in the washings of 



