18 MICROSCOPICAL OBJECTS FOUND 



object. I have also seen it in the guano from 

 Ichaboe. 



Fig. 5 may be only an elongated variety of 

 Grammatophora Africana. I have received it 

 from Dr. Bailey amongst some objects obtained 

 at Smyrna, where it occurs along with the true 

 G. Africana. I have never seen it on our own 

 coasts, though G. Africana is not uncommon ; 

 hence it may possibly be distinct. 



Striatella. (fig. 11.) This is apparently a 

 slight variety of the S. arcuata found on our 

 own coasts. 



Fragillaria. (fig. 12.) Long chains of frustules 

 occasionally occur. They are analogous to some 

 of the fossil forms called Bacillariae. The genus 

 is met with in both fresh and salt water. 



Gomphonema. (figs. 13, 14.) This is also a 

 marine as well as a fluviatile genus, in which the 

 frustules are generally supported on a long and 

 flexible stem or pedicle. I have observed two 

 species, both diff'erent from those which occur on 

 our own coasts. Fig. 13 may possibly be G. 

 geminatum, which it closely resembles. It is a 



