1866. | Loology and Animal Physiology. 305 
and Hancock, that “the Ascidians, Brachiopods, and Polyzoa pre- 
sent a number of common characters.” The indefatigable manner 
in which this naturalist is working is really such as to call forth 
some acknowledgment from us. During the past year he has pub- 
lished a very large number of most valuable papers and essays in 
both the ‘ Comptes Rendus’ and the ‘ Annales.’ 
M. Balbiani records some very curious observations on the eggs 
of various Invertebrata, in the ‘Comptes Rendus’ for December. 
He states that he has observed canals traversing the substance of the 
vitellus, and in connection in some forms with the contractile vesicle 
which he discovered some time since. M. Balbiani’s observations 
are so very remarkable that it is difficult to receive them with full 
assurance until they have been confirmed by other observers. He 
endeavours to point out that in ordinary animal cells there exists a 
contractile vesicle and canals connected with it, similar to the con- 
tractile vesicle and canals of the Infusoria. The author's observations 
were made principally on the eggs of Geophile longicornis, but 
also on those of the Dog, Ray, Batrachians, Annelids, Turbellarians, 
and Mollusca. 
Phthiriasis and the Pediculi may not appear to be very inviting 
objects of study, but at the same time, it would have been expected 
that the anatomy of the Louse had been completely made out by 
the researches of some of our early microscopists. | Leeuwenhoek, 
in 1694, remarked, “ Praeterea pro certo habentes adhuc millenas 
in capite pediculi esse res, que oculos nostros semper latebunt,” 
and it appears that he was right; for, even with the muicro- 
scopes of the present day, the mouth of the louse still remains a 
subject of discussion. The valuable series of papers of Dr. Leonard 
Landois, in Kélhker’s ‘Zeitschrift, have brought the anatomy of 
these interesting parasites again before the notice of zoologists, and 
now we haye a paper by Professor Schjédte, of great value, published 
in the Danish language, but happily translated by Mr. Dallas in the 
‘Annals of Natural History’ for March. The earliest observers con- 
curred in regarding the louse as a blood-sucking parasite, provided 
with a haustellum and not capable of inflicting a bite. Erichson, 
Simon, and Landois, however, contend that there exists a pair of hori- 
zontally working mandibles, true organs of biting, both in P. capitis 
and P. vestimenti, and in Phthirius inguinalis. Some cases of phthi- 
riasis are brought forward by Dr. Landois in his papers to support 
this view. Professor Schjédte, however, attacks this opinion very 
vigorously, and points out that the three authors who support the 
bitmg theory have been misled by their method of examination, 
which has led them into discrepancies with regard to the existence of 
“hooks” or “ palpi.” Our author remarks that, according to these 
three authorities, we have a mouth consisting of the following parts : 
—(1) an haustellum, according to Erichson and Simon, provided 
