220 THE CHICAGO ACADEMY OF SCIENCES. 



(Geo. H. Pepper) ; Las Vegas, San Miguel Co. (Miss Mary Cooper) ; Grant, 

 Valencia Co. (Pilsbry); Albuquerque, Bernalillo Co. (Pilsbry and Ferriss). 



SOUTH DAKOTA: Lake Herman, Lake Co. (P. C. Freeman); Date, Perkins 

 Co. (Over). 



TEXAS: Sabine River, Greenville, Hunt Co. (Smith. Coll.); Rutterville, 

 Fayette Co. (Lea). 



GEOLOGICAL RANGE : Charcoal zone of the Pleistocene of Arroyo 

 Pecos, New Mexico (Cockerell). 



ECOLOGY : In the Nautilus, Vol. X, p. 96, I find the following 

 note: "Limnsea bulimoides resisting drought. Specimens of a very 

 short-spired form of this species were lately received from Mr. George 

 H. Clapp, with the following note : 'They were collected by my cousin, 

 George H. Pepper, from a water-hole that appeared to be dry most 

 of the year, near Farmington, New Mexico, on September 20, 1896, 

 and reached me, packed in cotton, on October 5. On the 4th of this 

 month (November) I dropped them into warm water to soak them 

 loose from the cotton, and about two dozen out of 50 or more came 

 to life. They had been out of water 45 days! The shells spend nearly 

 as much time out of the water as in it, frequently crawling to the top 

 of the glass in which I keep them.' Out of 4 specimens sent alive, 

 packed in dry cotton, one revived at once upon being placed in water, 

 after an additional journey, dry, from the 6th to the 9th of November. 

 The survivor has a translucent or almost water-colored body, closely 

 peppered with opaque white; eyes black; tentacles opaque white; a 

 dark stripe on back starting between tentacles. With the Lymnseas 

 were some of the little bivalve Phyllopod crustacean, Estheria mexi- 

 cana Claus." (H. A. Pilsbry.) 



REMARKS: Cockerclli may be distinguished by its very globose 

 form, short and very broad spire and by the wide expansion of the 

 inner lip, which is not folded but broadly expanded, producing a large, 

 deep umbilical chink. It is a very characteristic and usually an easily 

 separable variety of bulimoides. Some specimens are narrower and 

 higher in the spire than the types (especially in specimens from Ogal- 

 lala, Neb. (pi. XXVIII, fig. 4), but all agree in having the open um- 

 bilical chink, expanded columellar region and dome-shaped spire. The 

 aperture varies somewhat in rotundity. It is probable that some of 

 the references under bulimoides and adelmce belong here, as both this 

 form and techclla have been recorded as bulimoides. Specimens from 

 Ventura County, California, show a tendency to vary toward the te- 

 chella form of shell, clearly showing that the cockerelli race is an 

 offshoot of techclla. (Compare plate XXVII, figures 33-35, with plate 

 XXVIII, figures 6-7.) 



