364 DR. GWYN JEFFREYS ON THE MOLLUSCA OF THE [May 20, 



the late Mr. Arthur Adams and my friend Captain St. John, aud 

 I cannot detect the slightest difference between any of them in shape, 

 coloured band, umbilicus, or dentition of the pillar. P. Iceviuscula 

 of the Crag has no umbilical perforation ; otherwise the recent and 

 fossil species are exactly similar. Some of the recent as well as 

 Crag specimens, and those of P. plicosa (if this be not the same as 

 the Crag species) have the throat or inside of the outer lip thickened 

 and crenated, as in Odostomia condidea and other species of that 

 genus. It must be borne in mind that species of different genera 

 are common to the North Atlantic and North Pacific Oceans, as well 

 as to the Crag, e. g. Pecchiolia acuticostata. 



Mathilda quadricartnata, Brocchi. 



Turbo quadricarinatus, Brc. Conch. Foss. Subap. ii. p. 375, t. vii. 

 f. 6. 



M. quadricarinata, Kobelt in Jahrb. d. d. Mai. Ges. 1874, p. 226, 

 t. ii. f. 2, 2 a . 



' Porcupine' Exp. 1870 : Atl. St.'off C. Sagres, 26-30, 36 ; Med. 

 50, 50 a , Benzert Road, Rasel Amoush, Adventure Bank. 



Distribution. Bay of Biscay (' Travailleur ' Exp. 1881), Mediter- 

 ranean and Adriatic, Madeira (Watson) ! ; 8-227 fms. 



Fossil. Miocene: Maine et Loire (Baudin), Malaga (Duncan). 

 Pliocene : Antwerp Crag (Omalius), Biot, and Italy. 



A Sicilian specimen, kindly sent me by the late Professor Aradus, 

 measures nearly an inch and a quarter in length and y^ of an inch 

 in breadth. The sculpture of this species varies considerably, and 

 this has, of course, given rise to several synonyms, including Eglisia 

 tnacandrea of -A. Adams, and two or three so-called species of 

 Brugnone. 



The correct position of the genus Mathilda, O. Semper, 1865, is 

 rather questionable. It certainly approaches Turritella in some 

 respects ; and my only reason for placing it provisionally in the 

 Pyramidellidce is the heterostrophe or sinistrorsally spiral apex. I 

 have thought it desirable to give (Plate XXVII. fig. 9) a magnified 

 figure of this character. 



I subjoin a description of the animal taken from a living specimen 

 during the ' Porcupine ' Expedition of 1870 : — Body cream-colour : 

 tentacles thread-shaped, smooth, very long and slender, bluntly 

 pointed, and diverging : eyes proportionally large, seated on small 

 tubercles or bulbs on the outer side of the tentacles about one fourth 

 from their base : foot large, in front deeply bilobed with remarkably 

 long auricles, behind angulated on the upper part and rounded at 

 the tail or extremity ; the foot-lobes are jagged inside, and double- 

 edged in that part with a row of close-set short and exquisitely fine 

 cilia which are in continual motion : operculum chitinous, rather solid, 

 multispiral with umbilicated whorls, like that of Turritella terebra. 

 Animal active and bold. 



