36 THE NAUTILI'S. 



order, for convenience of reference, no doubt, for Mr. Call has else- 

 where acknowledged and used the natural system of placing allied 

 forms in groups. A number of the species, especially those of La- 

 mark, are illustrated by carefully drawn wood cuts, the original and 

 additional descriptions are given. 



Lamarck's types were only briefly described by him in the 

 Animaux sans Vertebres, and were not figured, and as he had but a 

 limited amount of material on which to base these descriptions, and 

 many of his localities were erroneous much of his work naturally rests 

 under a cloud. Lea examined most of what were believed to be his 

 types of Naiades, and it is on his testimony that our identifications 

 of the species of the great French Naturalist, for the most part, rest. 

 The determinations of the Lamarckian species given in this paper 

 agree with those of Lea. 



Mr. Call has long been known as an extensive collector and a 

 careful student of the North American Unionidoe, a.nd is deservingly 

 considered a high authority on the subject. The only criticism on 

 his paper that occurs to the writer of this review is that one or two 

 errora are made in identification, and that he has placed rather too 

 many .-pccies in the synonymy. Uni<> lircri<l<'ns is not the male of 

 what Lea afterwards described as ?7.arTe/orwm, for although closely 

 allied it is perfectly distinct. The former in its younger stages is 

 more compressed, and the remarkable swelling in the posterior region 

 of the female is always full and distinct, projecting below the base 

 of the shell. N. arcwformi* is always greatly inflated, is more 

 strongly angled posteriorly, and the swelling of the female shell is 

 nut so distinct, nor does it usually project below the ventral line. 

 It is not colored like V. br< n<li:n*. 



L'niii i'< mistits Lea is a solid shell, with broad, distinct, green rays, 

 and is probably only a heavy form of ('. .<ji<ii<il,iiti.t, while U. /itm*! 

 Marsh, is more delicate, and has indistinct, wavy hair-line radiations 

 of dull green, and a general reddish tint thoughout the shell. 



In general the synonymy is quite correct, and Mr. Call has made 

 a good move in I lie direction of checking the enormous multiplica- 

 tion of specific names that are founded on mere variations nr insuf- 

 ficient material. The paper is a valuable and welcome addition to 

 the literature of the North American Unionithe. C. T. SIMPSON. 



At a special meeting of the trustees of the Detroit Museum of 

 Art, held June 25th, a bronze medal was presented to Mr. Frederick 

 Stearns, in recognition of his valuable gifts and untiring efforts on 

 behalf of the Museum during the past twelve years. 



