ADDENDA ET CORRIGENDA. 



The following Diatomaceous earths referred to in the present volume, 

 are to be added to the list given in Vol. i. p. 5 : — 



Mull Deposit. Described by Dr. Gregory in the Transactions of the Mi- 

 croscopical Society for 1853 ; and in the Quarterly Journal of Microsco- 

 pical Science, vol. ii. 1854. 



Newbie Deposit. Described by Professor Harkness in the Edinburgh 

 New Philosophical Journal, July 1855. 



Page 12, add to the description of Himantidium pectinate : var. /3. Frustules with internal 

 cells. Blarney, Co. Cork, March 1856. 



12, line 8 from bottom, for undulatum read undulata. 



28, line 2, for never read rarely : authentic specimens of Achnanthes Capensis sup- 

 plied by Dr. Arnott, and which are identical with my A. brevipes, have stipes 

 occasionally longer than the frustules. 



43, insert a reference to Plate XLII. 315, for Grammatophora serpentina. 



66, to the habitat of Mastogloia Grevillii add, Gill Banks near Ulverstone, March 

 1856, Miss E. Hodgson. 



In Plate LXI., last line, for maculatum read macilenta. 



