•210 



Mi.iNiKIIiAPn OF BKITISH LAND ANP FRESHWATER MOLLUSCA. 



Arion hortensis Ferussac. 



1S19 

 lS-26 

 1 s."),-i 

 l>S(it) 

 1 STH 

 1870 

 ISSl 

 1 SS3 

 ISSil 



is:i4 



IS! 17 

 IS-.M 



I Mis 



is7;i 



Arion hortensis l'\i 

 linc'ffiis ]ii 



issae, Hist. Moll, p. (i."), pi. 

 Hist. Nat. Eur. Alerid., p. 



ff. 4, 



(P)vj/,7<M)/«.v,vK Moq.-Tana., Hist. Moll. France, p. 14, pi. 1, ff. 28-30. 

 anflirai'ins Itdiirg., Moll. uouv. lit., etc., p. 178, pi. '20, ft'. 8-10. 



prlupliil u!i Mabille, Ann. Malac, p. 117. 



— dixtijichis Maljille, op. cit. , p. 110. 



— ])i/iriiiiirii.s- Fafjot, in Gourdon. Moll. Luclion, p. 82, 



— (('//iliiiis Fitz. , ISyst. Verz. Oesterr. Weielitli. 



— cuttUnuts Pollonera, Contr. Stndio .-l/'/o// Eiirop., 



— rlniiiiiil IIS C'ollinye, Ann. an<l .Maj;. Nat. Hist., p. 



— ,11 nihil-: ('ollin;,'e, Proc. Zool. Si>r., p. 444, pi. 31, 

 Limii.r siilifii.viifi PfciH'er, Syst. Anonl., p. 20. 



PnilriiiK Iioiinisi.s M.alni, Limac. Scaml., |i. 49, jil. 2, f. ."i. 

 Knbrlf'ni hortrnsiK Scil)ert, Xachr. Deutscli. Mai. (tc^. , p 



p. 14, ir. 2.3, 

 ti(i, pi. oa. 

 Vi. is, 10. 



81. 



I^ISTORY.— Jr/»/f hiirti'ii^h (hor- 

 tensis, a garden) wa.s first foainl 

 ill tliis cijimtry ill 1S17, by l)r. Leach, 

 wlio placed .specimens in the National 

 Uollection ; its occurrence was, how- 

 ever, not published until 1S2I, when 

 Dr. Gray added the species to the 

 British list in the pages of the 

 Medical Repository. 



It is probably in part the Lhmi.r 

 fdscintus of Nilsson, and according to 

 Ferussac the vestigial shell is the 

 Li)>i((reUi( ciincuvii of Brard. 



This species has been separated 

 from Arion ufer and ^1. siih/itsciis by 

 jMo([nin-Tandon and others, and placeil 

 in a grouji Prolepis, which is chai'acter- 

 iy.ed by jiossessing a more completely 

 formed shell than is said to be present 

 in the two former species. This 

 character is, however, ([iiite illusory, 

 as is also their separation based upon 

 the modification of the genital atrinin, 

 as [iroposed by Dr. Simroth. 

 This speci(\s is associated with Mi-. E. J. Lowe, F.K.iS., of Shircnewtou 

 Hall, Chepstow, the famous fern specialist, and author of many esteemed 

 works thereon, in acknowledgment of the excellence of his "Conchology of 

 Nottingham," ]mblished in 1,S,'):-!, and of his e.Kceiitional knowledge of the 

 .sjierific characters and habits iif our British slugs. 



Diagnosis. Arion //orfmsis may bi> distinguished fiom Arion utrr 

 a,n(l Arion snlifiisriis by its much smaller size and ditl'erent shade of 

 colonring. h'rom Arion ciri'umscripfKs it is separable by its tough, 

 leathery iiifcgiimenl., its more slender foi-ni, orange foot, black dorsum, 

 a,nd the mniv indistimOly defined bla.ck lateral binds, which are also 

 less ilorsally pl;i,ced than in that sjiecies. 



