6 FIELD MUSEUM OP NATURAL HISTORY ZOOLOGY, VOL. XIV. 



National Museum, the American Museum of Natural History, and the 

 Museum of Comparative Zoology. To the officials of these institutions, 

 especially Dr. J. A. Allen and Dr. G. M. Allen, acknowledgment is grate- 

 fully made. 



The accompanying illustrations are from drawings made by several 

 different artists. The line drawings of muscles and soft parts (Pis. IV-X) 

 are the work of Mr. Robert E. Snodgrass, now of the U. S. Bureau of 

 Entomology; the wash drawings of skeletal parts (Pis. XI-XVIII) 

 were done by Mr. Kenji Toda of the Department of Zoology, University 

 of Chicago; the illustrations of the brain (Pis. XXI-XXII) are by Mr. 

 A. B. Streedain formerly of the Department of Anatomy, University of 

 Chicago; and the drawings of external parts (Pis. I-II) are by Mr. L. L. 

 Pray of Field Museum. 



HISTORY. 



In a brief list of mammals from Ecuador published by R. F. Tomes 

 in 1860, the following note appeared without reference either to genus 



or species: 



"A small animal about the size of the Water Shrew (Soreoc fodiens), 

 with external characters and incisor teeth so much like those of the 

 Soricidae as to have led in the first instance to the belief that it was a 

 placental Insectivore, perhaps in some degree resembling the Solenodon 

 of Cuba. However, the existence of a small and rudimentary pouch 

 sufficiently attests the implacental nature of the creature, which but for 

 this must certainly, as far as external appearances go, be regarded as one 

 of the Soricidae. A more ample account of it will be given on a future 



occasion." 



This is the first published reference to the animal now known as 

 Ccenolestes. Three years later (Tomes 1863), the single immature speci- 

 men was described as to its dentition and external characters and 

 given the name Hyracodon juliginosus without any reference to its affin- 

 ities within the order of marsupials. Subsequently it received little 

 notice for many years. In 1880, Alston referred to it in the following 

 brief statement, published as a footnote (Alston 1880, p. 195): 



"A small Marsupial from Ecuador, named H yracodon fuliginosus by 

 Mr. Tomes (P. Z. S. 1863, p. 51, pi. VIII), may represent a distinct 

 family, but it is still only known from the very unsatisfactory original 

 description. In any case it will require a new title, the name Hyracodon 

 having been applied to a genus of fossil ungulates by Professor Leidy 

 in 1856, seven years before its use by Mr. Tomes." 



