300 BRACHIOPODA. ’ 
To give even a succinct statement of the conflicting views of 
the authors first mentioned would unduly increase the number 
of my pages; those who wish to pursue the subject further may 
read with interest and profit : 
E. 8. Morse.—American Journal of Science and Arts, p. 100, 
July, 1870. 
Proc. Bost. Soc. Nat. Hist., xv,.1873. 
Memoirs Bost. Soe. Nat. Hist., ii, 29, 1871. 
Wm. H. Dall.—Am. Jour. Conchology, vi, 88, 1871; vii, 39, 
1872. 
A. Agassiz.—Review of Kowalevsky’s Memoir, Am. Jour. of 
Science and Arts, 3d ser., vill, 470, 1874 (Kowalevsky 
published in Russian). 
F. Stoliezka.—Paleontologica Indica, vol. iv, Brachiopoda. 
Davidson’s paper, ‘‘ What is a Brachiopod?”’ may also be con- 
sulted by those desirous of reading a fuller account of the group 
than is given in these pages. Geological Magazine (London), 
for 1877; or a French translation in Annales de la Société Mala- 
cologique de Belgique, x, 1876. 
The Brachiopoda (= Order Palliobranchiata, Blainville, 1814) 
are bivalve molluscoids, which differ from the ordinary mussels, 
cockles, etc., in being always equal-sided and never quite equi- 
valve. Their forms are symmetrical, and so commonly resemble 
antique lamps, that they were called lampades, or ‘ lamp-shells,” 
by the old naturalists (Meuschen, 1787; Humphreys, 1797) ; the 
hole which in a lamp admits the wick serves in the lamp-shell for 
the passage of the pedicel by which it is attached to submarine 
objects. 
The valves of the Brachiopoda are respectively dorsal and 
ventral; the ventral valve is usually largest, and has a promi- 
nent beak, by which it is attached, or through which the organ 
of adhesion passes. It is sometimes perforated, as in the Tere- 
bratulide. The dorsal or smaller valve is always free and 
imperforate. The valves are articulated by two curved teeth, 
developed from the margin of the ventral valve, and received by 
sockets in the other; this hinge is so complete that the valves 
cannot be separated without injury. A few genera have no 
hinge; in Crania and Discina the lower valve is flat, the upper 
like a limpet; the valves of Lingula are nearly equal, and have 
been compared to a duck’s bill. 
This and several other points of difference seem to show the 
propriety of adopting the proposal made by Deshayes in 1836 of 
