ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
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vascular bands and septa ; its cavity is divided into two principal com- 
partments by a longitudinal median septum ; the other septa are so 
arranged that a mould of the cavity exactly represents a racemose gland, 
the two chief lobes of which are determined by the large median septum. 
The green or cortical substance has neither the form ascribed to it by 
Grobben or by Wassiliew, but is a glandular plexus formed by canals, 
which anastomose among themselves on a uniq[ue plan. These canals 
give off diverticula, which swell out into ampullae which form the 
vesicles of the green substance. The author accepts Wassiliew's account 
of the white substance, but absolutely denies the accuracy of the more 
recent statements of Szigethy and of Rawitz ; and the same remarks 
apply to the communications between the constituent parts themselves. 
We may regard the excretory apparatus of the Crayfish as formed of 
a septate sac tending to be racemose in form ; of a glandular plexus 
which occupies the whole of the lower surface of the gland ; of a 
twisted transparent tube ; of a large white spongy cord ; of a large 
bladder ; and of an excretory canal. 
Monstrilla.* — Mr. G. C. Bourne has some notes on this genus of 
Copepoda. Nearly all j^revious writers have regarded Monstrilla as a 
parasitic form, for no other reason than the absence of mouth-parts and 
alimentary tract. But every specimen that has been caught has been 
found in a free pelagic condition. The well-developed swimming feet, 
with their powerful musculature, and the total absence of any, except 
sexual, grasping organs, combine to speak against a parasitic habit. It 
is possible that Monstrilla may present an analogy with the Ephemeridae, 
and the adult may be preceded by a predaceous larva having mouth- 
parts and an alimentary tract which, after a succession of rapid ecdyses, 
developes into the mature sexual form, whose only function is that of 
reproduction. Mr. Bourne acknowledges, however, that the undoubtedly 
young specimens which were taken by Dr. Norman afford no support to 
this suggestion, except that some of them have rudiments of gnathites 
which are entirely absent in adults. The Monstrillidae may be regarded 
as a separate subfamily of the Corycieidse. A new definition of the 
genus is given and six species are recognized ; of these M. longispinosa 
from Plymouth is new. 
Entomostraca of Bay of Marseilles.! — Prof. P. Gourret has a note 
on this subject. His recent researches have enabled him to increase 
the number of known Copejioda by twelve ; fourteen Cirripedia are 
registered ; the only known Ostracod is Cypridina mediterranea Costa, 
and two species of Podon are the only Branchiopods. 
Vermes, 
a. Annelida. 
Polynoida of Spitzbergen.J — Herr H. Trautzsch gives an account 
of eleven Polynoids collected at Spitzbergen, one of which only — 
Harmothoe vittata — is new. He afterwards proceeds to discuss their 
nephridia. He finds that, in their simplest condition, they are tubular 
* Quart. Journ. Micr. Sci., xxx. (1890) pp. 565-78 (1 pi,), 
t Arch, de Biol., ix. (1889) pp. 472-83 (2 pis.), 
j Jenaisclie Zeitsclir. f. Naturw., xxiv. (1889) pp. 61-104 (2 pis.). 
