179 



On Hyalodiscus subtilis [Syn. Craspedodiscus Frank- 

 LiNi). By William Hendry^ Esq._, Sur-^con, Hull. 



Having in possession several slides of this diatom presented 

 me through the kind liberality of Mr. Harrison and George 

 Norman Esq., of Hull, containing entire shells and fragments 

 of exquisite beauty, some of which constitute part of a gather- 

 ing obtained from seaweed direct from the hands of the late 

 Professor Bailey (Harrison), and having examined my entire 

 stock with all care and attention, and under varied modes of 

 manipulation, reversing the slides, and thus obtaining several 

 aspects of each particular shell, so necessary in the examina- 

 tion of all fine and complicated striation, having also referred 

 to Professor Bailey's published plates ('Smithsonian Contri- 

 butions,^ vol. vii, Feb., 1854), furnished me by Mr. Harrison, 

 as well also to my subscription copy of Pritchard^s ' Infusoria,^ 

 plate V, fig, 60, both these latter being magnified by a hand 

 lens of f to 1 inch focus, I find circumstances attending the 

 subject which appear worthy of a more extended inquiry, and 



Hyalodiscus subtilis {si/n. Craspedodiscus Franklini). 

 Arc of Eadiation. 



Axis of Illumina- 

 tion and 

 Decussation. 



Axis of Illumina- 

 tion and 

 Decussation. 



Arc of Radiation. 



to merit a rigid examination by more able and experienced 

 microscopists than myself, who may possibly possess speci- 

 mens more favorable for conclusive interpretation, than 

 such as with the few materials I have at command, I am alone 

 able to submit on the present occasion. 



