1. 



K- 



J.AMKJUUBRANCHIATA. 29 



Sais is only a variety of P.viireits Cheniii. ') Uii the one hand, there are all transitions from the densely 

 scaled to the perfectly smooth specimens; on the other, we find specimens which have just as thin valves 

 and just as small ears as P. abyssoruvi in combination with a sculpture such as we find in /'. vitrcus. 

 Distribution. The investigations of the "Ingolf" show that Pcctcii vifrnis does not enter into 

 the "cold" area, but keeps to places with positive bottom-temperature (2.4"— 6° C.) in the southern jjart 

 of the Davis and Denmark Straits, also south round Iceland over to the Faeroes, in 136 to 975 fm. 2) 

 On the European side the species ranges from Lofoten along the Norwegian coast, 50 — 650 fm. (Sars), 

 into the northern part of the North Sea, ca. i5ofm. ("Thor") and down into the Skager Rak, ca. 240— 

 350 fm. i"Thor"). Further, it occurs between the Faeroes and Hebrides, 229— 650 fm. ("Lightning"), off 

 the west coast of Ireland, France and the Pyrenean Peninsula, 90 — 994fm. ("Porcupine"), in the Bay 

 of Biscay, ca. 340 — 895 fm. ("Caudan"), N. of the Azores, 2240 fm. ("Travailleur-Talisman"), at the 

 Azores, ca. 445 — 840 fm. ("Princesse Alice") 3), at the Canaries and W. of Morocco and Soudan, ca. 85— 

 iioo fm. ("Travailleur-Talisman"), Sargasso Sea, 1650 fm. (id.) as also in the Mediterranean (to Sicily). 

 In the Western Atlantic it occurs off Nova vScotia and Newfoundland, 57— 4oofm. and further .south 

 as far as Florida, going down to a depth of 1537 fm. off Chesapeake Bay (Verrill). It has also been 

 taken off the west coast of Patagonia, 140 — 400 fm., at the Philippines, 100 — 700 fm. and at the south 

 of Japan, 345 fm. ("Challenger"). 



Pecten similis Laskey. 

 Pecten similis Laskey, Mem. Wern. Soc. I, iSii, p. 387, pi. 8, fig. 8; Jeffreys, Brit. Couchol. II, 1863, 

 p. 71, PI. 23, fig. 5. 

 At Iceland the "Ingolf" has taken this species at: 



St. 98. W. of Iceland 138 fm. 5.9° C. 8 valves 



. 86. - - — (Brede Bugt) 76 - 6 — 



- 87. - - — — no - I — 



- 85. S.W. - — 170 - I .spec, and 15 valves. 



- 6. S.E. - - 90 - 7-o° C. 3 - 



The largest of these specimens (vSt. 98) measure: length 7™"', height 6.25""". 



Further, P. similis has been taken S. of Iceland at 



63' 15' N. L., 22^" 23' W. L. 170— 114 fm. Numerous spec, 

 as well as at the following places at the Faeroes: 



Klaksvig 10-15 fm. 2 valves. 



Fnndingsfjord 12— ca. 20 - coarse sand 23 — 



Vestmanhavn 5—6 - fine black sand 2 — 



6r 40' N. L., 7° 40' W. L. 135 - 5 - 



1) In his great work on the MoUusca from the "Exped. scient. tUi Travailleur et du Talisman" (T. II, 1898, p. 398) 

 .\. Locard maintains the opposite view. 



2) Posselt records a specimen from Sukkertoppen (almost in the same latitude as St. 28 of the "Ingolf) at 15 — 

 20 fm., but the specimen has certainly not been living at this shallow depth. 



3) It can be seen from the figures, that Chlamys Chaperi Dautzenberg and Fischer (1. c.| is identical with the 

 present species. 



