BBACHYPODELLA, S. STR. 81 



apex is truncate, about 9 whorls remain. Pfeiffer examined 

 specimens in Ferussac's cabinet, and found that his collaris 

 and antiperversa are merely extremes of a single species, and 

 he adopted the former name; but, for reasons given below, I 

 do not think his course a tenable one. 



The spire when entire is attenuate above (Vol. XV, pi. 64, 

 figs. 15, 16). The first whorl is much elevated, though de- 

 pressed at the tip, as shown in the figures, fig. 16 representing 

 the apex revolved 90 degrees to the right of the position shown 

 in fig. 15. The plug is at the end of the sixth whorl, and that 

 many are ordinarily lost by adult snails. 



Helix (Cochlodina) collaris was enumerated by Ferussac 

 in his Tableau Systematique, p. 61, no. 507. His specimens 

 were said to be from Porto Rico, collected by Mauge. He 

 gives no description, referring merely to Lister, pi. 20, f. 4, 

 and a copy of the same figure in Petiver's Gazophylacii 

 Naturae, etc. This figure is very rude, but probably repre- 

 sents B. costata, as the shell is stated by Lister to be from 

 Barbados, and no other species has been found on that island. 



In the Animaux sans Vertebres, vi, pt. 2, p. 114 (April, 

 1822), Lamarck refers to Ferussac, repeats his references, 

 and defines the species under the name Clausilia collaris: 

 " Shell fusiform-subulate, very acute, longitudinally and 

 obliquely striate, reddish; whorls very numerous; aperture 

 small, rounded, toothless. Length 6i/> lines." He gives the 

 same locality and collector, but as some of Mange's other 

 localities have proven erroneous, too much dependence should 

 not be placed upon them. 



In interpreting collaris we are confronted with the follow- 

 ing conditions: (1) Helix collaris Ferussac was not defined 

 by him except by reference to a figure representing a Bar- 

 bados species, probably B. costata. This was the first use 

 of the name collaris for a Brachypodella, as is proven by 

 Lamarck's citation of the Tableau in his synonymy. (2) 

 Clausilia collaris Lam. was not defined with sufficient pre- 

 cision to identify the species; he repeats Ferussac's reference 

 to Lister. (3) It is certain, in the light of information and 

 figures published later, that the form actually before Ferussac 



