DALL: MOLLUSCA AND BRACHIOPODA. 391 



gonia, Coutliouy; Port Rosario and Wolsey anchorage, 17-30 fatlioms, Alert 

 Expedition. 



This species seems extremely abundant, and the hundreds of specimens col- 

 lected by the " Albatross " enable the full range of variation to be traced, from 

 which the above synonymy results. The color varies from nearly black to light 

 yellowish brown. There is a small angular pallial sinus. There is no chondro- 

 phore, and, while a small gap intervenes between the anterior and posterior rows 

 of teeth, the resilium, which seems to be obsolete, does not occupy it. The liga- 

 ment doubtfully passes in front of the beaks, unless as a mere functionless film. 

 I have compared Gould's type, still preserved in the National Museum, with the 

 " Albatross " specimens. The species differs from the type of Tindariopsis 

 (T. agathida Dall) in possessing a small angular pallial sinus, and might therefore 

 be put in a separate section if such tine discriminations be regarded as desirable 

 in so variable a group as this. 



That this species, belonging to a different genus from Risso's shell, was erro- 

 neously referred to Leda, does not oblige us to reject the name of Couthouy and 

 Gould. 



PHASEOLUS Jeffreys. 



Phaseolus (Jeffreys MS.) Monterosato, Atti Accad. Scienze, Palermo, 1875, pp. 4, 11 

 (nomen nudum); von Martens, Zool. Record for 1875, p. 205; Jeffreys 

 (olim) P. Z. S. Lond., 1879, p. 673; Seguenza, Nucul. Terz. Ital., 1877, 

 p. 1182; type, P. ovatus Jeffr. 



Silicula Jeffreys, P. Z. S. Lend., 1879, p. 573; type, S./rapilis Jeffreys. /. c, p. 574, 

 pi. 45, figs. 6, Ca; Seguenza, Form. Terz. de Reggio, 1879, p. 284; Verrill, 

 and Bush, Am. Journ. Sci., 1897, ser. 4, 3, p. 62. 



Jeffreys* manuscript name Phaseolus, applied to one or two fossil species from 

 the Italian tertiaries, was printed by Monterosato and Seguenza before Jeffreys 

 himself had given a diagnosis. The sole example of the genus illustrated by 

 Seguenza in 1877 was P. ovatua. Apparently without knowing of this publica- 

 tion, in describing a recent shell from the Porcupine expedition dredgin?s, in 

 1879, Jeffreys substituted for his original manuscript name another, Silicula, 

 with a single species S. fragilis. These shells, though having rather a similar 

 hinge, are otherwise quite unlike, so that in 1897 Verrill proposed to retain both 

 names as follows, the characters having been recast from authentic specimens. 



Phaseolus (Jeffreys MS.) Seguenza, type P. miatus Jeffreys. 



Shell short-ovate, the hinge subequal on each side of the beaks, the two series 

 meeting at an obtuse angle under the beaks, valve practically equilateral; no 

 pallial sinus, ligament? teeth lamellar, few, subequally divided. 



Silicula Jeffreys, type S. fragilis Jeffreys. 



Shell very inequilateral, beaks at the anterior third, calyculate ; an oblique 

 chondrophore and internal resilium, external ligament obsolete; hinge line nearly 



