SCIENCE-GOSSIP. 



69 



" limber up," and go in search of something for the 

 inner man, but our first application met with the 

 answer "too late!" though more successful at 

 the next establishment, where we soon lost our 

 appetites and just managed to catch a late train 

 home, and the microscope was brought into 

 requisition to determine the character of the 

 suspects. Two of them proved to be females, and 

 the others the insect so long and laboriously 

 searched for, the male of Prestwichia aquatica. It is 

 anything but " the better half," being a small flea- 

 like creature, barely three-quarters of a millimetre 

 long, and, as I surmised in Science-Gossip, ante 

 p. 41, apterous. It is of a brown colour, the 

 antennas are similar in shape and in number of 

 joints (seven) as those possessed by the female. 

 The tarsi, three joints, thus confirming the opinion 

 of the late Prof. J. O. Westwood (Linn. Trans, 

 second series, vol. i, "Zoology," p. 588, first line). 



It is almost too early to express an opinion as to 

 the host of this aquatic parasite, but from the 

 comparative delicacy of the legs, and great length 

 of the ovipositor, I incline to think we shall find it 

 parasitic in some of the quiescent pupae rather 

 than the eggs or larvae of aquatic insects. So very 

 little is known of the habits and economy of these 

 animals that we must be prepared to have our 

 nerves shaken by some new facts turning up in the 

 course of our investigations, and I cannot too 

 firmly impress upon all naturalists the very great 

 importance of making most careful drav/ings and 

 descriptions, to avoid errors being promulgated and 

 handed down from generation to generation. 



21, Manor Gardens, London, N. ; July xoth, 1896. 



FORMULATION OF SHELL- 

 BANDS. 



r^ ONSIDERING the ease with which a collection 

 of British five-banded land-shells may be 

 made, and the interest and beauty of such a col- 

 lection, the wonder is that more persons do not 

 enter upon the study. Perhaps this is to be 

 accounted for by the difficulty of hitherto obtaining 

 a convenient check and label-list, with instructions 

 how to proceed. It is a study which would repay 

 investigation, for little has been systematically 

 done. 



The subject has now been made easy by the 

 compilation of such a list ("A Label-List of the 

 Varieties of the British Five-banded Landshells, 

 with the Band Formulae for Helix nemoralis and 

 Helix hortensis," by John T. Carrington.) This 

 twelve-page pamphlet supplies a long-felt necessity 

 for shell collectors who, like Mr. Carrington, have 

 made the subject of band variation a special study. 

 The nomenclature of varieties followed is that of 



the Conchological Society's list of 1892, with some 

 varieties added, not that this exhausts the number 

 of varietal names published ; for instance, not one 

 of the seven varieties mentioned by Mr. T. D. A. 

 Cockerell in the " Nautilus," iii. (1890), p. 139, is 

 included, although, with the exception of var. 

 subglobosa, Binn., they are all stated to occur in 

 Europe, and probably in Great Britain. Mr. 

 Carrington has, perhaps, exercised a wise discretion 

 in reducing the number of varieties, as many un- 

 doubtedly are merely mutations or monstrosities. 



Several attempts have been made to classify and 

 catalogue the different combinations of bands, as 

 observed in these two species of Helix. Some of the 

 more noteworthy are: G. von Marten's " Ordnung 

 der Bander an den Schalen von Landschnecken," 

 (1832) ; J. Sauveur in " Memoirs Soc. Mai. Beige," 

 ii. (1867), p. 59; F. Reibisch, " Allgem. Deutsch. 

 Naturh. Zeitung," N.F., i. (1855), p. 283; S. 

 Clessin, " Jahrb. Augsb. Naturh. Ver.," xxii. (1873) ; 

 Max Kunze, " Nachr. Bl. Deutsch. Malak. Ges.," 

 xi. (1879), p. 55; C. Ashford, "Journ. of Con- 

 chology," iii. (1880), p. 89; C. Riemenschneider, 

 "Nachr. Bl. Deutsch. Malak. Ges.," xiii. (iSSij ; S. 

 S. Pearce, "Journ. of Conchology," vi. (1889), p. 

 123; T. D. A. Cockerell, "The Nautilus," iii. 

 (1889), p. 75; G. K. Gude, "The Field " (1891) ; 

 T. D. A. Cockerell, "The Nautilus," viii. (1894), 

 p. 92 ; and many others of minor importance. 



The system adopted in the list now under con- 

 sideration is a decided improvement on its 

 predecessors, as any given formula can be found 

 without the slightest difficulty, and, speaking from 

 experience, this is more than can be said of any of 

 the other lists. The whole being printed on one 

 side of the paper only, it will be found to form a 

 handy label-list for practical purposes as well as 

 an exchange list to circulate among conchologists. 

 The low price of one penny brings it within the 

 reach of the poorest collector of land-shells. 



We note with a sense of pleasure that this list is 

 remarkably free from blemishes, which — remem- 

 bering the quantity of numerals used, each species 

 numbering eighty-nine formulae — is saying a good 

 deal. In looking through it and checking it with 

 the writer's own list in " The Field " of 1891, we 

 have found only two misprints, i.e. of Helix 

 nemoralis, the first formula of 4 bands in 3 should 

 read 4 bands in 2, o(23)(45) ; and of Helix 

 hortensis, after the last formula of 4 bands in 2, one 

 is omitted, i.e. 4 bands in 2, o(23)(45), while 4 

 bands in 3, 023(43) occurs twice, and one should 

 therefore be deleted. 



On the second page of this pamphlet are full 

 though simple instructions for studying the band 

 formulae. We have no hesitation in cordially 

 recommending this list to all conchologists inte- 

 rested in this subject. 



G. K. GuDE. 



