VAN DEE HQEVEN’s ZOOLOGY. 
85 
so, however, than in the present enlightened age we could have thought 
possible. Indeed it would have been better if the translator had used 
some slight discretion, and embodied in the first volume well-known 
patent facts, which are very inconveniently alluded to by him in the pre¬ 
face to the second. The classification of the animal kingdom, as taught 
by Huxley, is one that recommends itself to all unprejudiced judges, and 
we would give here its leading details, in order that, making them a 
standard, we may be the better able to compare that given by our 
author in the present volumes:—1. Yertebrata = (a) Abranchiata (in¬ 
cluding Mammalia, Aves, and Beptilia). (/3) Branchiata (including 
Amphibia and Pisces). 2. Mollusca, divided into—(a) True Mollusca, 
and (/3) Molluscoidea = Polyzoa, Tunicata, and Brachiopoda. 3. Annu- 
losa: (a) =Insecta, Myriapoda, Arachnida, and Crustacea. (/3) An- 
nuloidea = Echinodermata, Annelida, Botifera, and the flat-bodied and 
nematoid worms. 4. Coelenterata (including zoophytic and acalephoid 
forms). 5. Protozoa = Sponges, Bhizopods, and Infusoria (true). "We 
shall begin to notice the last in this list, as it is the first with Yan der 
Hoeven; and, as we go along, shall add to the bibliography such recent 
information as may suggest itself to us, and has either escaped the notice 
of the translator, or been too recent to be included by the author. 
The Infusoria of Yan der Ploeven includes the Bhizopods and true In¬ 
fusoria. In the preface to the second volume Dr. Clark refers to an order 
of minute parasites, the Gregarinse, which may be arranged after the Bhi- 
zopoda. They were discovered by Leon Dufour in the intestines of insects. 
Here we may mention a paper by Schmidt on their history and deve¬ 
lopment, in the first volume (1855) of the “ Transactions of the Sen- 
chenberg Society of Naturalists.” Yan der Hoeven makes no mention 
of the sponges; but the observations lately published by N. Lieberkuhn, 
on the development of the fresh-water Spongilla, have induced Dr. Clark 
to mention (in the preface to the second volume) that many authors are now 
disposed to refer them to the animal kingdom. With such tardy confessions 
before us, we do not feel disposed to wonder at the time it took to con¬ 
vince the scientific men of the eighteenth century of the animality of 
the Corals. While refusing' admission to the Sponges, the author includes 
Yolvox and other Algee among the animals. Many important details 
about the Infusoria are given in a paper, by Mueller, in the “Proceed¬ 
ings of the Boyal Berlin Academy of Science” for 1856. Passing to the 
Coelenterata, represented by the two classes Polypi and Acalephae, we 
find arranged under the first, as a section, the Bryozoa. Yan der Hoeven 
errs in stating that this title was given by Ehrenberg in 1828, the truth 
being that J. Y. Thompson’s name of Polyzoa was bestowed in 1830, and 
Ehrenberg’s not until 1834. 
The position of the Polyzoa, as a section of the Polyps, is most unfor¬ 
tunate. We do not at all agree with Dr. Clark when he states that as 
many objections can be urged against placing this class near the Tunicata, 
as are urged against keeping it in union with the Anthozoid type, and 
we would gather from the work that the author will shortly be of the 
right way of thinking in this matter. We remark that both author and 
