LAMEI.LIHRANCIIIATA. 



103 



K\- far the great uiajorit\- of ilu- West Icelandic specimens bcloni;;- to tlie typical A. Montagtti'^). 



Thus, all the specimens from the southern part of the west coast belong to the txpical form, 

 as will be seen from the following examples: 



Height Breadth 



Locality Length Height S— Breadth 



Length Length 



Grundarfjordr 18.3 '""'. 17 ■""'. 92.9 "/^ 10 """. 54.6 ^i^ 



- 17 - 157 - 924 - 9 - 52-9 - 



Engey 17.2 - 15.8 - 91.9 - 8 - 46.5 - 



Hafnarfjordr 17.2 - 16 - 93 - 10 - 58.1 - 



— 16.5 - 15.8 - 95.8 - 10 - 60.6 - 



E. N. E. of Helganes 13.5 - 13 - 96.3 - 7.5 - 55.6 - 



Keflavik 14 - 13 - 92.9 - 7.5 - 53.6 - 



The typical A. Montagui also occurs on the northern part of the west coast, but by side of 

 it we find moreover somewhat more elongated specimens, which approach to or may be entirely re- 

 ferred to the variet\' striata: this is seen from the following measurements: 



Height , Breadth 



Locahtv Length Height Breadtli 



Length Length 



Talknafjordr 18.2 "'"'. 16 ">">. 87.9 "/^ 9 """. 49.4 % 



— 16.8 - 15.2 - 90.5 - 8.5 - 50.6 - 



— 15 - 14 - 93-3 - 8 - 53.3 - 



Patreksfjordr 19 - 16.5 - 86.8 - 



— 17 - 15-2 - 89.4 - 8.75 - 51.5 - 



15-7 - 14 - 89.2 - 8 - 51 - 



— 14 - 13 - 92-8 - 7-5 - 53-6 - 



South Iceland: 



Vestmannaeyjar 30 fm., gravel. 5 valves. 



— 49 - , clay with a little mud. i spec. & 40 valves. 



63°24' N. L., i7°5' W.L 70 - 2 valves. 



The maximum length of these specimens, which belong to the topical /{. Montagjii^ is 14""". 



Faeroes. 



Here the species is common at depths of ca. 5 — 50 fm. The maximum length is 19.8"'"'. 

 The various localities are as follows: 



\'iderejde 10 fm. i spec. & 6 valves. 



Klaksvig 10—15 " i — & 7 — 



I) A specimen from Grundarfjordr is even so high and short, with the posterior margin sloping so steeply, that it 

 resembles the form figured bv Brown under the name of Crassina obligua (lUustr. Conchol. Great Britain and Ireland, 1827, 

 PL 18, fig. 6), but in the second edition of his work given as a variety of Crassina striata (lUustr. Rec. Conchol. Gr. Britain 

 and Ireland, 1844, p. 96, PI. 38, fig. 6). Its inea.surements are a.s follows: height 17.5 '""'., length 17.5"!'"., breadth 10.5 mm. 

 This characteristic form also occurs at the Kieroes. 



