50 THE NAUTILUS. 



variations, which was the author's intention rather than to define the 

 species, although many of these are treated as species. His species 

 credited to Martini and Meuschen will have to be ignored, but those 

 of Bolten will stand. 



I have been led to write these notes in connection with my at- 

 tempt to list the collection of the late John Ford. In making com- 

 parative studies I have also used the collection of the Boston Society 

 of Natural History, thus having large series of all the more variable 

 species. With the combined collections, I have before me over 250 

 specimens referable to the following species and varieties. 



OLIVA SERICEA (Bolten). 



Porphyria sericea Bolten, Mus. Boltenianum, p. 33, 1798. 



Oliva textilina Lam., Ann. du Mus., p. 309, 1810. Bolton's and 

 Lamarck's species are both based upon the same recognizable figure 

 by Martini (Conch. Cab. II, tab. 51, fig. 559). Bolton's being the 

 first name proposed will have to be adopted, as was done by Marrat. 

 Why Tryon should have chosen the doubtful irisans described oi> 

 page 310 instead of textilina on page 309, making the latter a variety 

 of the former is hard to understand. Lamarck's first figure referring 

 to irisans is that of Martini (Conch. Cab., fig. 561). He again re- 

 fers to the same figure under reticularis (Ann. du Mus., xvi, p. 314). 

 Bolten refers to the same figure (561) as a second example of sericea^ 

 evidently considering it the young of that species. One feels doubt- 

 ful as to the identity of this figure; unbiased I should have referred 

 it to a light-colored sanguinolenta. The second figures referred to 

 by Lamarck are those given by Chemnitz (Conch. Cab., x, tab. 147,. 

 figs. 1371, 1372). This reference is followed by a question mark. 

 The latter figures certainly do not belong to this variable species, but 

 possibly to a form of ehgnns. Both Weinkauff and Marrat seem to 

 have selected the callous spired forms of zeilanica as the representative 

 of Lamarck's irisans. As the callus spire is not mentioned in the 

 original description or shown in the figures referred to, they are evi- 

 dently in error, as was pointed out by Ford when describing crypto- 

 spira (Proc. Acad. Nat. Sci., 1891, p. 98). 



It is probable that the progenitor of all the forms of this variable 

 species is tremulina from which diverge three well-marked varieties 

 with a number of parallel variations connected by intermediate forms,, 

 but the rules of priority compel the adoption of one of the extreme 

 variations. 



