8 
REVIEWS. 
covering, in hair, wool, and feathers, is more favourable to their production 
and development. A low degree of organic activity, and slowly-digestible 
food, favour the development of ecto-parasites; and hence they are more 
frequent in the carnivora. 
Animals subsisting upon the endosmosed juices of the tissues of other 
animals and plants, are rarely infected with parasites, as hemipterous 
insects, aphides, &c. Entozoa themselves are not infested. 
In the list of “man’s fellow-lodgers” are enumerated 26 Entozoa, 13 
Ectozoa, and 10 Entophyta. 
The most extensive associated flora and fauna, discovered by Dr. Leidy 
within animals, exist with wonderful uniformity within the intestinal 
canal of the Myriapod, Julus marginatus (Say), and the Coleopterous insect, 
Passalus cormitus (Fabricius). But we must refer our readers to the 
valuable pages of the work itself for the history of these wonders, and to 
Dr. Leidy’s beautiful plates, illustrative of them; and we are sure that 
their perusal will amply repay those who are interested in the study 
of these curious forms; and we hope will incite others to follow in his 
footsteps, and add somewhat to the list already furnished by those who 
have turned their attention to it. 
The Natural History of the Birds of Ireland, Indigenous and Migra¬ 
tory, CONTAINING DESCRIPTIONS OF THE HABITS, MIGRATIONS, OCCUR¬ 
RENCE, and Economy of the two hundred and sixty-one Species 
comprised in the Fauna. By John J. Watters, Associate Member of 
the University Zoological Association. Dublin: James M c Glashan. 
London : W. S. Orr & Co. 1853. 300 pages, 12mo. Price 5s. 
To the late Mr. Thompson, of Belfast, we are indebted for what may be 
appropriately termed the first Irish Ornithology, as, strange to say, though 
Ireland abounds in naturalists, comparatively little has yet been done 
towards the publication of a regular fauna. Within the last few years, 
however, considerable advances have been made in the right direction. In 
most of the larger towns, as well as in the metropolis, Natural History 
Societies have sprang up, and those whose efforts were, previously, at best 
but desultory, have been brought together; fresh energy has been infused, 
and the materials are being rapidly quarried from which we may soon hope 
to see future explorers amply provided with text-books, recording what 
has been observed throughout the land. 
The preparation of local lists has long and deservedly been acknowledged 
as a most important step towards attaining any just idea of the natural 
