260 
BRITISH ENTOMOSTRACA. 
Of late years, much more has been done by the con- 
tinental zoologists to extend our knowledge of these 
curious little creatures. Otto, in the ‘Nova Acta Natur. 
Curios./ 1828, Burmeister, in the same work for 1881, 
Kroyer, in his ‘ Tidsskrift/ 1888-9, and M. Edwards, in 
the ‘Ann. des Scien. Nat./ 1888, and in his ‘Hist. Nat. 
des Crust./ 1840, have given us a great deal of extremely 
interesting information with regard to their habits, ex- 
tended our knowledge as to the number of species, and 
brought forward a variety of startling facts respecting the 
young, and the curious changes of form they undergo in 
their advance to maturity. In America, Pickering and 
Dana have studied carefully a species found abundantly on 
the common cod-fish of their coast ; and in a lengthened 
memoir in the ‘American Journal of Science’ for 1888, 
have given a most minute description of it, with abundant 
anatomical details. They do not appear to have followed 
up the hatching of the young animals; but Mr. H. 
Goodsir, in a paper in the ‘Edin. Philos. Journal’ for 1842, 
has contributed somewhat to our knowledge concerning 
the young of the common species found in Scotland. 
Anatomy and Physiology, 8fc . — The Caligi are generally 
of a more or less oval shape, and depressed. The body 
of the animal consists of two principal portions. The 
anterior, frequently much the larger, consists of an oval, 
shield-shaped carapace or buckler, which includes the 
head and greater portion of the thorax. The posterior, 
sometimes not a fourth part the size of the other, com- 
prises the remainder of the thorax and abdomen. 
The anterior or cephalo-thoracic portion is formed of a 
flexible coriaceous substance, usually transparent, and 
composed, according to Pickering and Dana, of two coats. 
On its fore part, which is obtusely rounded, we perceive a 
narrow plate, notched in the centre, and its posterior por- 
tion has generally a deep sinus on each margin. The 
dorsal surface is marked by several lines or furrows, which 
divide it into four distinct portions. These furrows are 
