THE NAUTILUS. 57 



and straight, the outer lip sharp but probably immature. Height 

 of shell 22 ; of spire 12 ; maximum diameter 10 mm. It was 

 collected at the Galapagos Island in 33 fathoms, sandy bottom. 

 Though evidently not full grown, the sculpture of this shell 

 would identify it at any age. (U. S. N. M, 96370) . 



F. (?) orcutti n. sp. Nuclear whorls lost, the remaining five 

 whorls solid, with appressed suture ; axial sculpture of rude 

 lines of growth and (on the last whorl eight ) obscure low ribs; 

 spiral sculpture of broad, somewhat irregular, straplike spirals 

 and much smaller spiral threads ; of the former there is one at 

 the suture followed by three or four threads ; two at the shoulder 

 closely adjacent, followed by two threads ; and four or five in 

 front of the periphery alternated by single threads ; the color of 

 the shell is light yellow brown with axial rows of dark brown 

 spots on the ribs, the aperture white : the outer lip is sharp, 

 with three or four obscure nodules within the aperture : a thin 

 white callus on the inner lip, the canal short and slightly re- 

 curved. Height of shell 17 ; of spire (without the nucleus) 

 10 ; maximum diameter 8 mm. 



It was collected at Mazatlan by C. R. Orcutt and resembles a 

 Latirus except that the pillar is without plaits. (U. S. N. Mus. 

 No. 252697). 



LASMIGONA SUBVIRIDIS CONRAD, REDIVIVUS. 



BY L. S. FRIERSON. 



Lasmigona subviridis, Conrad. Probably few conchologists 

 are aware of the validity of this name, since it occurs in no 

 synoptical list of Unionidss known to the writer. 



Rafinesque published a species, Unio viridis, in his Mono- 

 graph of 1820, a work virtually introduced to American con- 

 chologists by Mr. Poulson's translation in 1831. 



In the autumn of 1835, Mr. Hyde gave specimens of a Unio 

 from the Juniata River to both Dr. Lea, and Mr. Conrad. The 

 latter published the shell, with an excellent figure, on plate 9, 

 of his new fresh-water shell, under the name of Unio viridis ? 

 Mr. Conrad stated that he was uncertain whether this identifi- 



