ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
361 
There are only two parts — the funnel and the coiled canal — and both are 
derived from the mesodermic hemi-somites. Lebedinsky believes that 
the coxal glands of Arachnids, the antennary, shell, and coxal glands of 
Crustaceans and of Limulus, are all nephridia and thoroughly homo- 
dynamic. But perhaps they are not thoroughly homologous. They are 
derived either from the primary embryonic coelom or from the 
secondary coelom, aud these are morphologically different. In fact 
the homology of the glands raises the problem of the homology of the 
mesoderm among Arthropods. 
5. Crustacea. 
Deep-sea Dredging in the Indian Sea.* — Prof. J. Wood-Mason 
and Dr. A. Alcock deal, in the present portion of their communication 
with higher Crustacea only ; they establish the new family Psallido- 
podidae for a genus of Decapods, but they give no indications of what they 
regard as the most nearly allied of known forms. Various species of 
Acanthophysidae and Pandalidas are described or noticed. 
Accelerator and Moderator Nerves of Crustacea.f— MM. F. Jolyet 
and H. Viallanes have studied in the common Crab the arrangement of 
the nerve-fibres that accelerate and moderate the movements of the 
heart. The centre for the former is in the ganglion of the last maxilli- 
ped and first thoracic limb, and for the latter in the more anterior part 
of the sub-oesophageal mass. The cardiac nerve of the Lobster appears 
to be wanting in the Crab. 
Blue Colouring Matter of Blood of Crustacea.:}: — M. F. Heim finds 
that this colouring matter exists in a reduced and colourless, and oxidized 
and coloured state. The additional oxygen is easily removed by a 
vacuum, the passage of inert gases, heat, or reducing agents. Haemo- 
cyanin is not the only albuminoid substance in the blood of Crustacea, 
there are also serum and paraglobulins. It is, therefore, useless to try 
and prepare pure haemocyanin by dialysis. Copper cannot be considered 
as a constituent of the molecule of haBmocyanin, for it is wanting in 
about half the Crustacea. These are not the only points in which the 
author’s results differ considerably from those of his predecessors, for he 
notes several important points of distinction between haemocyauin and 
haemoglobin. 
Excretory Apparatus of Decapod Crustacea.§ — M. P. Marchal has 
published a detailed account of his observations on the excretory ajipa- 
ratus of the Decapod Crustacea. He describes it as consisting of saccule, 
labyrinth, and bladder ; the labyrinth is all that part of the gland which 
lies between the saccule and the bladder, and it may always be considered 
as derived from a sac which becomes complicated by the formation of 
traversing trabeculae and septa. As a rule, there is no tubular portion 
following the saccule ; this is a statement which is opposed to what is 
generally taught, but what is only a too hasty generalization of the 
results obtained from the lower Crustacea aud from the Crayfish ; the 
* Ann. and Mag. Nat. Hist., ix. (1892) pp. 265-75 (2 pis.); pp. 358-70 (6 figs.). 
t Cumptes Rendus, oxiv. (1892) pp. 189-91. J Tom. cit., pp. 771-1. 
§ Arch. Zool. Exper. et Gen., x. (1892) pp. 57-275 (9 pis.). 
