INTRODUCTION. 



IX 



derms from the Philippine Islands, from which most valuable information 

 respecting the geographical distribution of many species was obtained. 



At Frankfort, I examined the collections made by Riippell in the 

 Red Sea. 



At Stuttgart, Dr. Krauss allowed me the freest use of the collection 

 of Echini made by him at Natal. 



In the University Museum at Bonn I found the types of Philippi, as 

 well as those of Professor Troschel himself, to whom I owe this oppor- 

 tunity of examining them. 



To Professor Ehlers I owe the discovery of the original specimens of 

 Klein, the most valuable historical collection of Echini in existence, which 

 has served as the basis of all the names proposed by Leske ; and as they 

 are generally adopted, it has been of incalculable service in clearing up 

 a multitude of doubtfid points. Through his exertions the Senate of the 

 University of Erlangen allowed the collection to pass to America for 

 examination. 



At Neufchatel, M. Louis Coulon placed at my disposal many authentic 

 specimens which formed a part of the material of the Catalogue Raisonne. 

 A few other species were found at Geneva through the kindness of the 

 late Professor Pictet. M. de Loriol spent considerable time in examining 

 with me his valuable collection of recent and fossil Echini, among which 

 were some interesting species from Ceylon collected by Mr. A. Humbert. 



The basis, however, for the accurate determination of most of the species 

 of Echini was found in the collection of the Jardin des Plantes. There 

 are preserved the originals of most of the species of Lamarck, and all 

 the collections brought home by the great French Exploring Expeditions. 

 This collection formed the chief part of the material of Blainville, and 

 again of the Catalogue Raisonne, so that without a very critical exami- 

 nation of this collection no commencement could be made. 



Professor Deshayes allowed me to examine the collection of the Jardin 

 des Plantes as if it were my own, and all possible assistance was ren- 

 dered me in identifying the types by Messrs. Rousseau and Potteau, 

 whose long acquaintance with the collection made it possible to identify 

 many things of which the tradition must soon' be lost. 



Professor Lartet gave me the opportunity of examining the few re- 

 cent species described by D'Orbigny still preserved with the rest of his 

 collections in the Paleontological Department of the Jardin des Plantes. 



