28 Stodder, on Diatomacea. 



jecting papillae or tubercles^ as may be easily seen in oblique 

 examples. The whole group of Actinocycli and Eupodlsci 

 requires revision^ and I believe that Mr. Edwards intends to 

 undertake the task. 



We have quite abundant and variable Stauroptera aspera, 

 Ehr. = Stauroneis pulchella, W. S. Ehrenberg made a 

 sub-genus of those Stauroneis that were striated or marked ; 

 but improved instruments having shown that all the Stauro- 

 neis are marked^ and none smooth, the sub-genus should be 

 cancelled, but the original specific names should stand. 



There are a great many species of other genera, some of 

 which will undoubtedly prove to be new ; but these are not 

 worked up as yet, or I have not received Mr. Edwards's 

 results. There are also several new forms, whose position in 

 classification is as yet quite doubtful. 



The Sandwich Island slides in this parcel represent very 

 well the character of all the others examined, except perhaps 

 in the genera Nitzschia, Amphora, and Campylodiscus, which 

 have been found much more abundant in number and species 

 than here, some of the species of which will probably prove 

 to be new; spicules of sponges are very abundant. 



On the Zanzibar slides I have seen two specimens of an 

 Auliscus, probably new ; and several of an Isthmia, certainly 

 so. 



