COOKE : DISTRIBUTION OF PURPURA LAPILLUS. 199 



When we come to detailed investigation of tlie Japanese seas, there 

 is still less evidence for the occurrence of P. lapillus in Far Eastern 

 waters. Schrenck, E.eisen in Amur Lande (108), omits it from his 

 list; Lischke (70) does the same. Pilsbry's (100) catalogue admits it 

 only on the authority of Stearns from Hakodate, and of E. A. Smith 

 (below). A. Adams (1) mentions P. lapillus from different points in 

 Japanese seas, from Saghalien southward, but when we find that he 

 includes in his synonymy freycinetii, Desh., attemiata, Reeve (?), 

 analoga, Forbes, and squamosa, Lam., his evidence ceases to possess 

 value. E. A. Smith (109) included P. lapillus in a list of Gastropoda 

 brought from Japan by Commander St. John, R.I^., remarking that 

 "the Japanese forms of this Protean shell are as varied as those in 

 European seas". The actual specimens are in the British Museum, 

 and undoubtedly helong to freycmetii, Desh. 



The truth appears to be that there is no reason to believe that the 

 species which we call lapillus, L., occurs in any part of Eastern Asia 

 or North-West America. All the specimens from these seas hitherto 

 referred to lapillus belong either to freycinetii, Desh., or to one or 

 other of the AYest American P«r/?Mr(g which will be mentioned below. 

 It is quite conceivable that a relationship, more or less close, exists 

 between these groups and lapillus. When JSorthern Asia enjoyed 

 a milder climate, opportunity would be given for the passage of 

 littoral forms from the North Atlantic to the Xorth Pacific, and vice 

 versa. This may be lield sufficient to account for the presence of 

 closely allied, or even of identical species, in both these areas at the 

 present day. Even as it is, experts find it no easy matter to 

 distinguisli between lapillus and certain forms of freycinetii, and 

 between certain forms of saxicola, Val., and lapillus. Middendorff 

 goes so far as to remark : "It can hardly fail to be the case that on 

 the coasts of the North American Ice Sea passage-forms between 

 P. lapillus and P. freycinetii will be found in the future." But 

 a sufiicient time seems to have elapsed since the passage via Northern 

 Asia was closed for the forms on both sides to harden into what we 

 agree to call species, just as we find a number of ' homologous 

 forms ' on the two sides of tlie Isthmus of Panama. 



Aurivillius (6) distinguishes freycinetii from lapillus by the 

 prominence of the last whorl and the great size of the moiith, but 

 remarks on the similarity between certain forms of the two species. 

 Middendorff speaks of the long aperture, short spire, and more 

 impressed sculpture. Lischke particularizes, as points of difference, 

 the narrowing of the mouth in front, running into a long canal, the 

 strongly marked spiral ridges, the irregular longitudinal foldings on 

 the upper part of the whorls. He thinks Adams' lapillus is freycinetii. 

 Dunker (32) remarks that the description and figures of the type of 

 freycinetii are so different from certain Japanese specimens which are 

 before him, that he cannot believe they are freycinetii. Among the 

 specimens are several which he cannot separate from certain varieties 

 of lapillus, and accordingly he refers all his specimens to that species, 

 confessing himself still ignorant what freycinetii is. The truth is, 

 that, as Lisclike has pointed out, Deshaycs' type oi freycinetii was 



