MARINE DIATOMS OF THE PHILIPPINE ISLANDS 127 



NITZSCHIA GRAEFFEI Grunow 



(Cleve, W. I. Diat., p. 20, pi. 5, fig. 32; Grunow, New Species, Nitz., pi. 12 

 fig. 4.) 



NITZSCHIA GRANULATA Grunow 



(Cleve and Grunow, Arct. Diat., p. 68; Grunow, New Species, Nitz., pi. 12, 

 fig. 7; Van Heurck, Synopsis, pi. 57, fig. 5.) 



NITZSCHA INSIGNIS Gregory 



Plate 28, fig. 6 



(Gregory, Glenshira Diat., pi. 1, fig. 46; Peragallo, Diat., France, pi. 75, fig. 5.) 



The type form and several varieties were found, one of which is 

 here figured. 



NITZSCHIA LITTORALIS Grunow 



(Van Heurck, Synopsis, pi. 59, figs. 1-3; Peragallo, Diat., France, pi. 69, fig. 17.) 



The form common in the Philippine Islands is exactly that figured 

 in Van Heurck's Synopsis, plate 59, figure 1. 



NITZSCHIA MAJUSCULA Grunow 



See underlay, fluminensis Grunow. 



NITZSCHIA MARGINULATA Grunow 



(Cleve and Grunow, Arct. Diat., p. 72, pi. 5, fig. 93; Van Heurck, Synopsis, 

 pi. 58,^figs. 12-14; Peragallo, Diat., France, pi. 70, figs. 14-17.) 



It is noteworthy that the form prevalent in the Philippine Islands 

 is the one common also in Campeche Bay, namely, N. marginulata, 

 var. subconstricta Grunow, it being another example of the similarity 

 of these two floras; it is figure 12 above. 



NITZSCHIA OBESA Castracane 



(Castracane, Chall. Exp., p. 67, pi. 13, fig. 11.) 



I greatly question there being any essential difference between this 

 and Leuduger-Fortmorel's previously named N. granulosa (Diat. Ceyl., 

 pi. 3, fig. 37) . Coming from approximately the same part of the world, 

 the figures and discriptions of the two are remarkably alike. Cas- 

 tracane does not give the dimensions of his species, but says it is twice 

 as long as broad. The measurements by Leuduger-Fortmorel agree, 

 namely, 104 by 48. N. obesa is said to have fine decussating rows of 

 beading, and although a decussating order is not evident in the figure 

 of N. granulosa it must be discoverable in so evenly and closely set 

 beading as there indicated. Castracane's type came from the Philip- 

 pine Islands and I give his name, with the above statement that it is 

 probably identical with the Ceylan Island form. 



NITZSCHIA PANDURIFORMIS Gregory 



(Gregory, Diat., Clvde, p. 57, pi. 14, fig. 102; Van Heurck, Synopsis, pi. 58, figs. 

 1-3.) 



35035—25 9 



