840 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
and BJiizosolenia in which the calyptriform valve has a more or less 
developed mucro generally terminated by a bristle. 
A monograph of all the known species is appended. The new 
genus Guinardia is thus described : — Frustules cylindrical, ringed ; 
valves circular with an undulation at the margin and a rudimentary 
mucro. The species of Bhizosolenia are further classified under 
three sections, — Anuulatae with ringed frustules ; and Squamosae and 
Genuinae in which the frustules are composed of more or less 
rhombic scales. In the former section the scales are very numerous ; 
in the latter each section has not more than four, and generally only 
two. Many of the alleged species of Bhizosolenia belong to some 
other genus, or want an adequate description. 
Entogonia.* — M. P. Bergon publishes a monograph of this rare 
genus of fossil diatoms. In describing the structure he terms the 
“ central triangle ” of Greville the central portion, the “ broad border ” 
the marginal portion, and the “ pseudo-nodules ” appendices. A full 
description is given of each of these parts. The existing definitions -of 
the genus are somewhat modified, and the following is given as its 
diagnosis: — Valves usually triangular, rarely 2-, 4-, or 5-angular, con- 
taining an angular central portion rarely reduced to a simple straight 
line, and a marginal portion divided into compartments by false bands 
corresponding to internal septa; a more or less elevated appendix at 
each angle of the valve ; subjacent canals uniting in pairs into a tube, 
which terminates in an orifice at a greater or less distance from the base 
of the appendices. The species are classified under two groups, 
Inornatae (6 species) and Ornatae (10 species). Three new species are 
described, — E. Le Tourneuri and Temjoerei belonging to the Inornatae ; 
and E. Brunii to the Ornatae. 
Lysigonium.t — Dr. J. B. Toni reviews the characters of Link’s 
genus of diatoms Lysigonium , and proposes to limit it to three or four 
species, with the following generic diagnosis: — Frustula elliptica vel 
globosa, 2-3 ad articulos arete conjuncta, non carinata, valvae simpliciter 
punctatae. The subgenus Carinaria is erected into a separate genus 
Gallionella Bory, with the characters, — Frustula globosa vel elliptica, 
catenata, carinata (superficie junctionis convexa nec plana), valvae 
simpliciter punctatae. The genus Melosira is limited to the species with 
the following characters, — Frustula cylindrica, arete conjuncta, non 
carinata, subinde sulcis donata (superficie junctionis plana), valvae 
simpliciter punctata. The following diagnosis is given of Paralia , — 
Frustula cylindrica, ut in Melosira , valvae simul punctatae et areolatae. 
B. Schizomycetes. 
Internal Structure of Bacteria.^ — Sigg. A. Trambusti and G. 
Galeotti record some observations they have made on the internal struc- 
ture of a micro-organism, isolated from drinking-water, and cultivated 
on the usual nutrient media. Examination of the organism in hanging 
drops disclosed long bacillary and short ovoid forms, both of which 
* Le Diatomiste, i. (1892) pp. 83-90, 128-47 (3 pis.). 
t Bull. Soc. Imp. Nat. Moscou, 1891, pp. 71-5. 
% Centralbl. f. Bakteriol. u. Parasitenk., xi. (1892) pp. 717-22 (1 pi., 17 figs.). 
