12 
2. When the openings of the interior portion are arranged in 
alternate rows, they assume the hexagonal form; when in straight 
rows, then the openings are square or oblong. 
Three phototype plates accompany the article. <A very in- 
teresting feature is the resolution of Amphipleura pellucida into 
beads. The photograph of Pleurosigma angulatum shows that 
the opinion of the old microscopists was well-founded, and that 
the alveoles are really hexagonal. Dr. Van Heurck considers 
that the intermediate beads are produced by bad focusing of the 
alveoles. 
Diatoms—Thetr Nutrition and Locomotion. J.D. Cox. (The 
Microscope, x, No. 7). 
Ex-Governor Cox has long been a faithful student of the 
structure and life-history of diatoms, and has contributed sev- 
eral valuable papers upon the subject. In this paper he advances 
the following ideas: 
1. It is not necessary to regard the raphe as a part of the 
mechanism of nutrition, as the life-sustaining osmotic process 
goes on through the alveoles, whose imperfectly silicified tissues at 
top and bottom permit the process of nutrition to go on freely. 
2. The raphe is distinctively a part of the locomotive contriv- 
ance of diatoms, and it is probably the seat of aline of cilia work- 
ing ina groove which is a true cleft. 
Diatomees fossiles du Fapon. J. Brun et J. Tempére. (Mémoires 
de la Societé de Physique et d’Histoire Naturelle de Geneve. 
xxx. No. 9). 
This is an excellent monograph upon the fossil diatoms found 
in the cementstein of Sendai and Yedo, Japan. 
Accompanying the seventy-four pages of text there are nine 
phototype plates containing 135 figures. : 
It is an interesting fact that three of the new species figured 
in the volume, viz.: Tabulina Testudo, Brunia Faponica and 
Pleurosigma Hungaricum are also found in the recently dis- 
covered fossil deposit at Atlantic City, N. J. 
A Reviston of the Genus Aulacodiscus, Ehrenberg. John Rat- 
tery, M.A., B.Sc., F.R.S.E. Journal of the Royal Micro- 
scopical Society, June, 1888. Ee 
A Revision of the Genus Auliscus, Ehrenberg, and of some allied — 
