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SUMMARY OF CURRENT RESEARCHES RELATING TO 
appear to mature before they are over two years of age, and it is possible 
that the young arc not born until the mother is at least three years old. 
The food of Peripatus consists of insects, woodlice, and such like. 
They never seem to eat one another, and oven when kept without food 
they do not attack c-acb other or their young. When feeding, the 
movements of the animal are very graceful and deliberate. The antennee 
arc endowed with a high degree of sensitiveness, and they appear to be 
the medium of a sense analogous to that of smell. In securing its prey, 
Peripaius does not seem to use the slimy secretion, unless the insect 
appears likely to escape, or when it struggles violently. The secretion 
is ejected with sufficient force to project at several inches. When freshly 
emitted it is rather liquid, but quickly toughens in the air. Peripatus 
is a very sociable creature and loves to crowd with its fellows in genial 
lurking places. Mr. Steel has observed several of them around one 
insect feeding in perfect harmony. The skin is cast at apparently some- 
what irregular intervals, and the casting is pure white, the colour-pigment 
being situated entirely in the inner skin layer which remains. No 
external parasites have ever been noticed. 
The kind of vivarium in which Mr. Steel has been most successful 
in keeping his specimens alive consists of ordinary glass jam jars, with 
metal lids which slip or screw on not quite air-tight ; these are filled 
with lumps of moist earth and odd pieces of rotten wood. 
5. Arachnida. 
Comparative Morphology cf Galeodidse.* — Mr. H. M. Bernard was 
induced to undertake the study of this group in the belief that it would 
settle the controversy as to the affinities of the Arachnida. The author 
gives a detailed account of the anatomy of the various organs of the body, 
and, in a summary, attempts to elucidate the phytogeny of the group. 
This he does by going in order through the characters of their organs, 
and proposing a hypothetical reconstruction of the ancestral form. This 
reconstructed ancestral form appears to possess most of the specialisations 
common to the group in its least specialised condition. That there is a 
resemblance between Scorpio and the Eurypterids is obvious, but it is 
due, Mr. Bernard thinks, to convergence. He has shown, he says, 
abundantly that Scorpio is a specialised, and not a primitive form. If 
we trace it and the Eurypterids backwards, we find that they grow less 
and less like one another, instead of growing more and more like one 
another, as they should if they have a common ancestor — at last all 
resemblance between them completely vanishes. The existing Arachnida 
are compared with the hypothetical ancestral form, with the view of 
getting a measure of their respective specialisations. These various 
specialisations do not lend themselves to any genealogical arrangement. 
They diverge entirely from one another, and cannot in any way be 
deduced the one from the other. 
The author finally discusses the relation of his hypothetical form to 
other Arthropods, and comes to the cor elusion that the four great 
divisions of the Arthropoda are distinct specialisations of a Chretojmd 
type in no way deducible the one from the other. 
* Trans. Linn. Soc. London, vi. (189G) pp. 305-417 (8 pis). 
