122 



SCIENCE-GOSSIP. 



The species is said to be common and widely 

 spread in England, but if any description of this 

 tubular appendage within the stomach has been 

 published, it has not come under my notice. It is 

 easily possible, however, that the effects of the 

 rather conspicuous undulations may have been 

 mistaken for vigorous action of the stomachal cilia. 



The Brachionus developed in so great abundance 

 in a small aquarium during the January and Feb- 

 ruary of 1896 that they became visible to the naked 

 eye as a whitish mist, and could be collected .by a 

 pipette and transferred to a watch-glass until the 

 water became milky with them. The males were 

 abundantly produced, and many females were 

 carrying male eggs. 



COPEUS QUINQUELOBATUS (1). 



The two lateral canals meet in the posterior 

 regions of the ventrum, and unite to form a short, 

 common duct opening into the central portion of 

 the contractile vesicle, which is apparently double 

 but really single, the two lobes contracting and 

 expanding simultaneously. The stomach bears an 

 undulating, tubular appendage similar to that 

 within Brachiomcs baheri, the only differences 

 being the shorter length and the fewer lateral 

 undulations. I entirely failed to note this tube in 

 the first few specimens seen, and therefore failed 

 to include it in my description of the rotiferon. 

 The appendage may therefore be more readily 

 overlooked, especially when the stomach is gorged 

 with food, than I had supposed. The colour of the 

 body varies from a pale yellow to a yellowish-red, 

 or almost the tint of the blood in certain Oligochasta. 

 The tail and foot seem to be always colourless. 



The ilabeUiform flame-cells (" vibratile tags"') 

 are, in face view, marked by fine, radiating striae. 

 In side view the internal flickering movements are 

 seen to be produced by a narrowly ovate mem- 

 brane, attached by the attenuated extremity to one 

 of the antero-lateral angles of the cell, whence it 

 extends obliquely across the cavity, undulating 

 toward that branch of the lateral canal of which 

 the flame-cell is the termination. The membrane 

 is permanently twisted into a loose spiral, and each 

 margin is apparently thickened into a cord-like 

 edge. It is these margins which produce the 

 illusion of a double spiral as the undulations are 

 longitudinally transmitted. In face view three 

 semicircular cords are visible vibrating obliquely. 

 When the flame-cell presents its frontal edge to the 

 objective, it seems to show a slit-like fissure, 

 widest centrally and narrowing towards each ex- 

 tremity ; yet this cleft may be illusory, as the 

 tip-tilting of the cell is momentary only, and is, 

 therefore, speedily gone out of focus, while the 

 object itself is exceedingly minute. 

 (To be continued.) 

 (') Journ. Roy. Micr. Soc, June, 1896. 



THE VALUE OF VARIATION. 



By John T. Carrington. 



TN the amusingly flippant style of the " Superior 

 Scientist " (1), which unfortunately too often 

 disfigures the pages of our otherwise respectable 

 young contemporary, " Natural Science," is a short 

 notice in the September number of that journal 

 entitled "A Registry Office for Snails." This 

 style reminds one of the pomposity of that equally 

 superior person the Honourable Mrs. Pedant, the 

 vicaress in a country parsonage, when patronising 

 her husband's poorer parishioners. Our " Superior 

 Scientist " refers to a recently-published label list, 

 issued for the convenience of those who desire to 

 investigate the range of variation in certain five- 

 banded Helices occurring in Britain. The note is 

 evidently penned by a " closet naturalist," who 

 depends for his information on published or 

 unpublished lists, and is not experienced in these 

 variable animals in the flesh. As only a small 

 percentage of our readers will have had oppor- 

 tunity of seeing his note, it may be well to set 

 his remarks in review. He says ; 



" The meaningless record of variations, mis- 

 called ' varieties,' seems to afford a kind of concho- 

 logical 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 other had a turn at them. All appear 

 equally ignorant of the fact that it has been fully 

 donebefore by Sauveur (Ann.Soc.Mal.Belgique, ii.), 

 who first drew up the scheme of the eighty-nine 

 possible variations in five bands of Helix horte?isis 

 and H. nemoralis. The latest venture in the 

 undertaking is a ' Label List ' by the editor of 

 SciENXE-Gossip, Mr. J. T. Carrington, published 

 at the cost of a penny, that should rejoice the 

 heart of the zono-maniac. A page of introduction 

 is followed by a list of named ' varieties ' (save the 

 mark !) of Helix poniatia, H. nemoralis, and H. 

 hoYtensis. 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 vari- 

 ations. We have also seen an unpublished record 

 of thirty-three for the two species. 



*' Nobody, unfortunately, has yet gone to the 

 animal and endeavoured to show the origin and 

 cause of these bands on the shell, and whether 

 they have or have not any physiological bearing. 

 The subject is being left to the variety mongers, 

 whose goal must inevitably be a registry office for 

 snails." 



Before discussing this question further, I am 

 sure the Editor of " Natural Science " will permit 

 me to thank him for inserting the notice and the 



(1) I use this objectionable word in the sense indicated for 

 it by Dr. Albert Giinther, F.R.S. (Science-Gossip, N.S., 

 vol. i., p. 242). 



