492 Zoology. 
the phosphorescence in our seas to be exhibited with the same characters every year 
during the summer season, but it was interrupted in the waters of the channel 
(De la Manche) when the cholera morbus prevailed at Havre and its vicinity in 
the month of May, June, and July 1834. * Several naturalists of the French 
capital, who are in the habit of visiting our harbour from season to season, and 
who had been observant of the phenomena, confirm this remarkable fact ; and 
the whole city is witness to the sudden and very general mortality of the fishes 
kept in our preserves of brackish water which then occurred. All the eels and 
flat fishes came to the margins and died. M. Surivay examined with the microscope 
some drops of the water become a little putrid, and he ascertained that its slight 
blood-tinted colour depended on the increase of different kinds of infusory ani- 
malcules. 
The diffused phosphorescence observable in our seas during the summer, M. 
Surivay attributes to the prevalence of a minute species of medusa (Noctiluca 
miliaris,) which he has described and figured in Gueriris Mag. de Zoologie. 
Parmacella, Cuvier MM. Webb and Vanbeneden have attentively examined 
the American mollusca reputed to belong to this genus in the rich collection of 
the late Baron de Ferussac, and the result is the establishment of a new genus 
(Peltella) for their reception, the organic differences between them and those of 
the old continent being so considerable as to justify their separation. This divi- 
sion besides has the advantage of fixing in a precise manner the geographical dis- 
tribution of the two genera. The Parmacellse appear to belong more particularly 
to Northern Africa, one species only having been met with at the western extre- 
mity of Europe, and in one of the warmest regions of the Iberian Peninsula. We 
may then presume, that when the Limacidoe of the north of Africa are better 
known, the group to which they (the Pannacellae) belong will present a series of 
species similarly conformed, and replacing in those climates the slugs of our tem- 
perate regions. The European species is minutely described and figured in a late 
No. of GueriiCs Mag. de Zoologie. It was found on the hills of Alcantara be- 
hind Lisbon, feeding on the young shoots of Cochlearia acaulis, and is charac- 
terized as follows : 
Parmacella Valenciennii, corpore toto fulvo, reticulatim rugoso ; concha scu- 
tello obvoluta, tenui, diaphana, fragilissima ; spirse rudimento instructa, basi mo- 
taria amditu sinuata. Webb and Vanbeneden in Mag. de Zoologie. 
On the sexes of some Crustaceans It is to be observed that, in regard of sex, 
the Cancro'idea differ not only in being male and female, but there are also bar- 
ren or spurious females, of which the broadly-trigonate abdomen is narrower than 
in genuine females, although broader than in the males. These are not to be con- 
founded with young females whose abdomen, as in the Majacese, is flatter than in 
the adults, for of several species there are both barren and fruitful individuals of 
the same age. The Cancro'idea and Matuto'idea are hitherto the only families in 
which these sterile females have been noticed. Portunus (Neptunus) pelagicus, 
sanguinolentus ; (Amphitrite) gladiator, hastatoides; (Charybdis) miles, 6-den- 
tatus ; (Thalamita) truncatus ; Ocypode (Macrophthalmus) japonica ; (Helice) 
tridens ; Grapsus (Erischeir) japonicus; (Grapsus) marmoratus have afforded 
* The exact year, as well as the name of the author's place of residence, is omit- 
ted in the essay from which this notice is, extracted. 
