16 
DoNKiN, on Marine Diatomacea. 
as new, or new to Britain, in his various papers. III. Species 
entirely new, and for the first time described in the present 
paper. 
I. Species described in Professor Smithes ^ Synopsis.^ 
Amphora affiiiis. 
„ salina. 
Tryblionella punctata. 
„ acuminata. 
Cocconeis scutellum. 
„ diaphana. 
Eupodiscus Ralfsii, /3 sparsus. 
Actiuocyclus undulatus. 
Coscinodiscus radiatus. 
Nitzscbia spathula. 
„ reversa. 
„ closterium. 
Synedra superba. 
„ tabulata. 
Navicula pygmala, /3 minutula. 
„ palpebralis. 
„ Sraithii. 
„ punctulata. 
„ Jenneri. 
„ humerosa. 
„ didyma. 
„ crabro. 
]yra. 
Pinnularia distans. 
Pinnularia directa. 
Stauroneis pulchella. 
Pleurosigma formosum. 
„ elongatum, 
„ prolongatum. 
„ strigosum. 
„ quadratum. 
angulatum. 
„ sestuarii. 
„ balticum. 
„ hippocampus. 
Amphiprora vitrea. 
Biddulphia Baileyii. 
„ aurita. 
Gomphonema marinum. 
Achananthes brevipes. 
„ subsessilis. 
Rhabdonema arcuatum. 
„ minutum. 
Gramraatophora marina. 
„ serpentina. 
Melosira nummuloides. 
Orthosira marina. 
Isthmia enervis. 
The stipitate forms enumerated above^ I need not say_, 
were not gathered in their natural habitat on the sands ; but 
the frequent occurrence of their frustules, in such a locality, 
was a sufficient indication of their abundance on the larger 
AlgsBj with which the neighbouring rocks of the shore are 
covered. 
The beautiful and curious Biddulphia Baileyii was plentiful 
in several of the gatherings ; it seems to me to be a free 
species ; I have observed its frustules undergoing the process 
of self- division. 
Navicula Smithii is here a plentifal species ; N, Lyra is 
also very common in all its varieties ; N. crabro frequent ; 
and N. humerosa occurs abundantly in some localities ; it is 
a species variable in its outline^ but very uniform in its stria- 
tion ; its dry valve is colourless, thus differing widely from 
N, granulata, Breb. 
