47 



Icngtli and 20 in lieight (like tin.' one which is figuiud) ; the other one which is 

 belted has 37 inillini. in lens^th and 2S ii> heii^lit. British specimens, of 21 and 

 25 iniUini. in Itngtli, with 17 and 18 milliui. in height, have a smooth belt; 

 otlievs again ilo not show il. At üji, the shells are always beliiw 2il mm. in 

 length, the largest I have before me measnring 17.5 millim. in length, and 13 in 

 h( ight. It is the only one which has a slight trace of a belt. The proportion 

 of length to height changes from | to i. The number of teeth is much 

 more variable than 1 rind it noted. It sometimes goes down to S anterior teeth 

 ([losterior according to (iould) and IG posteriiu' (Gould's anterior). The shells 

 tpioted by Wood, Crag Moll. II, p. S3, in order to prove the wide vertical and 

 topographical range of the group Aciia, viz. a recent species dredged off the 

 Cape of GiMjd Hope, and the cretaceous N. bivirgata and ovnatissiuia. have — as 

 Wood liim.self says — no sjiecitic relationship with our shell. Their existence, 

 tlierefore, cannot have any value in deciding the question umler considera- 

 tion. As to N. Lyalli, the identity of Bell's specimen with N. Cobboldia; 

 is affirmed by AVood hiinscdf in the sup[)lement, p. 112. The Pacific shell 

 originally called so must, therefore, l)e very nuich lil;e our s[>ecies. The charac- 

 ters added liy Wood (ib. p. ll.'i) as belonging to the FaciHc shells are indeed not 

 to lie seen in the recent Hakodate sj^jcimens, nor in the fossils I had before 

 nie except in tlie very large and fnllgrown fossil s{)eciniens mentioned ab<)ve. 



N. (,'obboldia' is deeidi'dly quaternary in England, as AVood remarks in his 

 supplement, and did not die out there before the latter part of the gla.ial period. 



Lechi confusa Hauley. 



(Sosverby, Thes. vul. 3. |). ll'.i, pi. 228, f. 85. — Keeve Conch. Icon. 

 Livda, pi. 5, f. 24, bis.— Lischke. .Jap. Meeres-Conch vol. I([. p. 109.— 

 Syu. Nucula pella. Sow. Conch, ill. Nucula. f. 4, non. cett. j. 



The shell, posteriorly narrow and a little shorter than in tlu niuudi d anterior 

 porti(jn, concentrically striated, is very rarely found at 0]\. 



Yohlln arrtka Broderip. I'l. VI, f. 29. 

 (Broderip and Sowerby Zool. Journal No. 15, p. .359, pi. 15, f. 1. — Jlid- 

 <lendorf. M('-in. de I'Acad. de I'etersb , ]>. 544.— Syn. Nucula lanceolafa 

 Sow. WW Lamarck : Wood Crag Moll. H. p 88, pi. l(i. f. 1(!. and suppl. 

 p. 115; and sowerby, 1S17. iliii. Comb. pi. ISO, f. l.|. 



Without eidei ing uptai the question of the correctness of the denomination, I 

 reject tlie name ditferently used by Lamarck and Wood and give the usual n.une to 

 the sliell, (I few s|K'ciinens of whicli, reaching 34 nnu. in lenglli and 18 in iicight. 

 were foun<l at Oji. 'J'hes« specimens, widely differing from all the I'aiilic species 

 mentioned by fJouM, .StimpsDU elc , liave the oblicjne undulating scidpiure and 

 transversely elongated, posteriorly sliorteneil and narrow, anteriorly elongated and 

 rounded form Indonging to the species. All the other charicters (smootiiness of 

 the jtart next to the |K)sterior ujiper margin, solidity of hinge etc.) are present. 



