66 Mr. T. H. Withers on 
In 1913 the Geological Department of the British Museum 
acquired from Mr. H. T. Martin two cirripedes on a piece 
of chalk, which he had collected in the Niobrara series of 
Kansas, and which are referable to Stramentum haworthi, 
Logan, sp., a species undoubtedly congeneric with Loricula 
pulchella, G. B. Sowerby. The specimens looked unpromising 
enough when received, but careful development soon showed 
certain points of structure which enable us to add materially 
to our knowledge of this anomalous type. The same 
structural features had shortly before been discovered in the 
type-specimens of Loricula darwini, and it is on the com- 
bined material that the following study of the genus is 
based. 
History. 
Of this genus as many as nine species and two varieties 
have so far been described, and in most cases the species is 
known by more than one specimen. 
The first-discovered species, Loricula pulchella, G. B. 
Sowerby (1843), was founded on a single nearly complete 
specimen from the Turonian (Middle Chalk) of Cuxton, 
Kent. It was obtained by the late Mr. N. T. Wetherell, 
whose collection is now in the Geological Department of the 
British Museum, and the specimen is registered 59,150. 
Darwin (1851) gave a masterly description of this specimen 
in his Monograph. 
A few years later the species L. macadami was established 
by Wyville Thomson (1858) for a fine specimen from the 
Chalk of Antrim, and some obscure fragments of others of 
a group are said to be scattered through the matrix. This 
specimen supplements in many ways that of L. pulchella, 
and, although it added much to our knowledge of the struc- 
ture of the shell, it has not been referred to by any later 
author *. 
In 1878 W. Dames described a single specimen from the 
Cenomanian (Lower Chalk) of Lebanon, Syria, under the 
name J. syriaca, and the specimen was subsequently 
figured by Prof. Zittel (1884). 
K. A. von Zittel (1884), for a single specimen from the 
Senonian (Upper Chalk) of Diilmen, Westphalia, founded 
the species L. levissima. A plaster-cast of this is in the 
Geological Department of the British Museum, registered 
59,713. 
* R. Tate quotes the species among a list of fossils, Quart. Journ. 
Geol. Soc. London, vol. xxi. 1865, p. 30. 
