Feb. 15, 1883 | 
we find the orders Pauropoda and Onychophora, the latter 
for Lansdowne Guilding genus Peripatus, which, by 
the way, he referred in his original description to the 
mollusca, and not, as here stated, to the worms. 
The chapter on the Arachnida includes the Scorpions 
and their allies the Spiders, Mites, Tardigrades, and 
Pantopods ; in the sketch of the latter a half page might 
usefully have been devoted to recent researches on the 
distribution of this extraordinary group of marine forms 
in the depths of the sea. 
The class of Crustacea is well illustrated, and in the 
NATURE 
Fic. 2.—Millepora, showing expanded zooids. 
introductory chapter we have an excellent account of the 
general anatomy and strange development of the group. 
Even Fritz Miiller’s account of the metamorphosis of 
Penzus is given, with figures of the Nauplius, Zoea, and 
Mysis stages. The typographical arrangements of the 
headings of the orders of the Crustacea seem faulty. 
The Editor’s eye has failed him here, and though the 
sense is in no ways altered by the want of uniformity in 
the type used for the headings Brachyura (p. 197), Ano- 
moura (p. 202), Macroura (204), yet there is a utility in 
the case of a classification of appealing to the eye. The 
Fic. 3.—Zufplectella aspergillumt, structure. 
. 
King Crabs are placed as usual among the Crustacea, 
but the joint authors (Messrs. Dallas and Woodward), in 
their concluding remarks on the Arthropods write: “the 
structural relations of these to the scorpions would seem to 
be very close, and certainly raise a difficult problem, one 
which is rendered still more interesting by the fact that, 
according to the researches of Dr. Jules Barrois, a Limu- 
loid, or King Crab-like stage occurs in the development 
within the egg of certain true spiders. For the present, 
this and many other such questions must, however, re- 
main open. In all biological problems relating to the ! 
369 
past developmental history of the organic world, we must 
for a long time yet expect to come continually upon 
obscure and puzzling points which only a more extended 
knowledge of minute details can clear up.” 
The various classes of the “grand division” of the 
worms are treated rather unevenly. This grand division 
is, no doubt, a somewhat heterogeneous one. “ Thus it is 
found that an animal does not exactly correspond with 
one of the articulate groups, and another resembles in 
certain points, but not in all, an Infusorian. They are 
then placed with the Vermes [worms] because of the 
existence of certain fundamental structures.” There is a 
good deal of minute anatomical detail given about the 
Leeches and Rotifers, while the Land Planarians are 
dismissed with the following:—‘‘ They have eyes, no 
tentacles, a proboscis, and a narrow body. They are 
found in the United Kingdom and generally in Western 
Fic. 4.—Rhipidodendron splendidum. 
monad. 
A, colony ; B, two monads; ¢, free 
and Central Europe. They have been found in America 
and on continental as well ason oceanicislands. Moseley 
says that they are nocturnal in their habits, when in the 
light getting under leaves. Some contain chlorophyll and 
seek the light, but die in the sunshine. They eat small 
snails, worms, and flies. An American kind secretes a 
mucous thread, and suspends itself in the water, and 
another lets itself down from the leaves by one.” 
If we were introduced to the Worms as a Grand Divi- 
sion, we are told that the Echinoderms form a Sub- 
Kingdom of the Animal Kingdom, but there is nothing 
to guide us to this in the heading of the portion of this 
volume in which Mr. Herbert Carpenter so well, though 
succinctly describes this important group, an account that 
we would have wished to have been much more detailed. 
The classes of this group getting about three pages of 
text to each, and several of the pages are devoted to new 
and excellent woodcuts. 
The group of the Zoophyta embraces the Hydrozoa and 
