l6o NATURAL SCIENCE. September, 1896. 



draws the conclusion that stridulation is only exercised by the males 

 " with direct reference to females, or in rivalry to other males in the 

 presence of a female "; only in one species, Stethophyma fiisca, did the 

 males stridulate in the absence of the other sex. When the male has 

 secured a partner he, as a rule, ceases to make a noise. However, in 

 the small species Pezotettix pedestvis in which both sexes have vestigial 

 wings, and the male is accordingly unable to produce sound, he obtains 

 a female by " capture," jumping upon her back. While in that 

 position he moves his hind legs alternately, recalling, in Professor 

 Poulton's opinion, the lost power of stridulation. 



A Registry Office for Snails. 



The meaningless record of variations, mis-called " varieties," 

 seems to afford a kind of conchological small-beer to many collectors 

 of shells. The bands on certain British shells are a source of never 

 failing delight to some; whilst all have one time or another had a turn 

 at them. All appear equally ignorant of the fact that it has been fully 

 done before by Sauveur [Ann. Soc. Mai. Belgiqiie ii.), who first drew 

 up the scheme of the eighty-nine possible variations in the five bands 

 of Helix hortensis and H. nemoralis. The latest venture in the under- 

 taking is a ' Label List ' by the editor of Science Gossip, Mr. J. T. 

 Carrington, published at the cost of one penny, that should rejoice 

 the heart of the zono-maniac. A page of introduction is followed by a 

 list of the named "varieties" (save the mark!) oi Helix pomatia, H. 

 aspersa, H. nemoralis, and H. hortensis. The last four pages, printed on 

 one side only, are devoted to a repetition of the names of the last two 

 species, accompanied in each case by one of the band formulae. 



The worst of it is, that like the farmer with the claret, " no one 

 seems to get any forrarder," and no systematic use seems to have been 

 made of these tables. The only published account we know is that by 

 Mr. A. Belt [Report Ealing Micro, and Nat. Hist. Soc, 1892), who 

 proved the existence of twenty-seven out of the eighty-nine possible 

 variations. We have also seen an unpublished record of thirty-three 

 for the two species. 



Nobody, unfortunately, has yet gone to the animal and en- 

 deavoured to show the origin and cause of these bands on the shell, 

 and whether the}' have or have not any physiological bearing. The 

 subject is being left to the variety-mongers, whose ultimate goal 

 must inevitably be a registry office for snails. 



