1892.] ON THE CLASSIFICATION OF OPHIUROIDS. 175 



two species of Deer — Cariacus paludosus, frequenting the open 

 marshy spots, and Cariacus simplicicornis, inhabiting the woods; and 

 two Peccaries {Bicotyles torquatus and B. labiatus). Of Carnivora, 

 the Jaguar was the most frequently seen ; the Puma being equally 

 abundant but less conspicuous, owing to its inhabiting the open 

 campo. In the waters of the river near the mouth an Otter 

 (Lutra paranensis) was abundant. 



As the expedition proceeded farther up the Pilcomayo, the 

 channel became narrower, and a great fall in the level of the water 

 taking place, progress became much obstructed. Still, however, the 

 ' Bolivia ' struggled to get onward, but eventually came to a full 

 stop about 300 miles from the mouth of the river, in the midst of a 

 parched and salt-saturated country, consisting almost entirely of 

 open campo, in which animal and vegetable life of all kinds was 

 marked by extreme poverty and lack of variety. The greater part of 

 the men here deserted, the leader and the doctor both died ; and the 

 remainder, numbering nine in all, after a detention of over four 

 months, were ultimately rescued by a military search-party sent out 

 by the Argentine Government. Mr. Kerr was compelled to leave 

 the steamer ' Bolivia ' in the Pilcomayo, and with it the greater 

 part of his collections. The more portable portions — the bird-skins 

 and the plants — were brought off on mule-back. The birds have 

 been worked out, and an account of them has been published in the 

 'Ibis' for January 1892; while the Botanical collections are being 

 investigated at Kew. 



In illustration of his remarks, Mr. Kerr exhibited a series of 

 14 views taken from his own negatives, representing the progress 

 of the expedition, and the life of the district traversed by it. 



The following papers were read : — 



1. A Contribution to the Classification of Ophiuroids, with 

 Descriptions of some new and little-known Forms. By 

 F. Jeffrey Bell, M.A., Sec. E.M.S. 



[Eeceived February 15, 1892.] 

 (Plates XL & XII.) 



1. The Calyciual Plates of a young Ophiuroid, p. 175. 



2. The Classification of Ophiuroids, p. 176. 



3. Account of Ophioteresis elegans, g. et sp. n., p. 178. 



4. The Subdivisions of Ophiuroids, p. 179. 



5. The Eelation of Ophioteresis to Fossil Forms, p. 182 



6. The Radial Shields of Ophiomaza ohscura, p. 182. 



7. OpMobyrsa hystricis, p. 183. 



1. The Calycinal Plates of a young Ophiurid. 



Among the valuable collections recently made by Messrs. J. J. 

 Walker, R.N., and P. W. Bassett-Sraith, R.N., of H.M.S.'Penguin'S 



1 Forwarded to the British Museum through the Hydrographer. 



13* 



