PKOGRESS OF MICROSCOPICAL SCIENCE). 
85 
too short and meagre, mucli that has been done on the group receiving 
no notice whatever. Lastly, Pollen and Polycistina are capital papers, 
and Polyzoa is by no means bad. With these we must terminate our 
present notice. In our next we shall have a word to say on the sub- 
ject of the plates, and shall conclude our notice of the remainder of 
the volume. — To he continued. 
PKOGEESS OF MICKOSCOPICAL SCIENCE. 
Cup-cells of the Conjunctiva. — In a provisional communication to 
the ' Centralblatt ' (No. 47, 1874), Dr. M. Eeich gives the results of 
his observations on the cup-cells of the conjunctiva, which have pre- 
viously only received notice at the hands of Steida and Waldeyer. It 
is well known that these writers, as well as Max Schultze, thought 
that these cells were unicellular glands, and that they secreted the 
mucus, since they are found on all mucous membranes. V. Than- 
hoffer, however, who has particularly examined those present on the 
villi of the intestines, holds that they are ordinary columnar cells 
from which the protoplasmic contents have escaped. Reich finds 
that they are common on the conjunctiva of old people, and in slight 
catarrhal states. They were remarkably abundant in the conjunctiva 
of a young man who had suffered from sharp conjunctivitis in conse- 
quence of a very prominent staphyloma corneas. 
The Classification of the Animal Kingdom. — A paper on this subject 
was read by Professor Huxley before the Linnean Society at a recent 
meeting (December 4, 1874), which, however, was not completely 
written out, so that as yet no exact report of it appears. It was of 
much interest, since it speculated on the relation of the Amphioxus, 
and it to a certain extent admitted Professor Haeckel's division of 
animals into Protozoa and Metazoa. 
Development of the Teeth in Beptilia and Batrachia. — At the 
meeting of the Royal Society, on December 10, an important paper, 
by Mr. Charles Tomes, was read on this subject. He says that the 
descriptions given by Arnold and Goodsir of the development of the 
human teeth have been already demonstrated to be in material respects 
inaccurate as applied to man and other Mammalia ; and the present 
paper shows that the accounts propounded by Professor Owen, of the 
process in Batrachia and Reptilia, which are practically an extension 
of the theories of Goodsir to these classes, are even more at variance 
with the facts of the case. There is in no Batrachian or Reptile any 
open groove or fissure (" primitive dental groove ") ; there are, at no 
period of development, free papillae ; consequently, the whole process 
of "encapsulation" has not any existence, but is purely hypothetical. 
From first to last the whole process of tooth development takes place 
in solid tissue, beneath an even and unbroken surface ; with which, 
