PALEONTOLOGY. 395 



ledge of the specific forms, but could not add much to 

 Roemer's fundamental observations and influences. The illus- 

 trated catalogue of the British Museum contains an attractive 

 account of the present knowledge about Blastoids, written by 

 Robert Etheridge and Herbert Carpenter. 



The Sea-stars (Ophiuridea and Asteridea) offer far less 

 diversity f form than the Pelmatozoa. If we except a few 

 genera and species mentioned or figured by Goldfuss, Hage- 

 now, Mantell, Dixon, and others, the first scientific monographs 

 on fossil Asteridea were those contributed by Edward Forbes 

 on material derived from Cretaceous and Tertiary formations 

 of Great Britain. Wright afterwards described all the Meso- 

 zoic Asteridea, and Salter the Palaeozoic forms of Great Britain. 

 Mtiller (1855) and Roemer laid the foundation of the know- 

 ledge of Asteroid types in the Devonian formation of the 

 Rhine Provinces ; the Jurassic Ophiuroids and Asteroids of 

 Germany have been investigated by Pohlig, Fraas, and Georg 

 G. Bohm. J. Hall made known the representatives of this group 

 in the Palaeozoic formations of North America. The palaeonto- 

 logical literature in all cases closely harmonises with the zoo- 

 logical, and it would seem that the Palaeozoic " sea-stars " 

 differed very little from those in the seas of the present age. 



Fossil Echinids were already known in the beginning of the 

 eighteenth century, and received full attention in the oldest 

 systematic works by Breyn (1732) and Klein (1734). A 

 number of new species are described in the chief work of 

 Goldfuss, in Desmoulin's Studies (1834-37), and in Sismonda's 

 monographs on the fossil Echinidea of Piedmont and Nizza. 

 But the strictly scientific literature began with the researches 

 of L. Agassiz (1838-41) on living and fossil sea-urchins, along 

 with which appeared the monograph by Agassiz and Desor 1 on 

 the fossil Echinidea of Switzerland. Valentin's well-known 

 observations on the anatomy and histology of the genus 

 Echinus was contemporaneous with the important works of 

 Agassiz and Desor. 



1 Ecluard Desor, born 1811 in Friedrichsclorf, near Frankfort-on- Maine, 

 for a long time collaborated with Agassiz in palaeontological and glacial 

 studies, and followed Agassiz to America, but in consequence of some dis- 

 agreement between the friends, Desor returned to Neuchatel and became 

 the Professor of Geology in the Neuchatel Academy. Inheriting consider- 

 able means from a brother, he retired to Combe Varin, in Val Travers, 

 and devoted himself to geological and pre-historic studies; died on 23rd 

 February 1882, in Nizza. 



