1910.] NATURAL SCIENCES OF PHILADELPHIA. 113 



variable, as in all the related species. Two of this lot are figured, 

 pi. IX, figs. 1, 2, 4, 5. In one or two shells there is the minute vestige 

 of a parietal tooth (figs. 4, 5). The soft parts were partially spoiled 

 when studied, but I have figured the terminal ducts of the genitalia, 

 pi. X, fig. 3. The spermatheca was broken. Other organs agree with 

 the type figured in 1905. 



The genitalia of two specimens are figured, pi. X, figs. 2, 5. The 

 penis and vagina conform in shape to the usual Chiricahuan type. 

 The retractor muscle of the penis is well-developed, but short, about 

 2 mm. long. The epiphallus is very long. Measurements of the 

 organs may be found on p. 97. The penis and epiphallus are decidedly 

 longer in three specimens of this lot dissected than in the type or 

 topotype of esuritor. The spermatheca of the types of esuritor is 

 unusually swollen distally, as correctly represented in the figure 

 published in 1905. 



Additional specimens (pi. IX, figs. 6, 7, 8) from the east side of 

 Barfoot Park, Station la, were taken by Mr. Ferriss in 1907. The penul- 

 timate and two preceding whorls have the fine stria? interrupted 

 irregularly, in places forming minute granules, and there is besides 

 some indistinct appearance of punctation on the spire. There are 

 very fine spiral lines on the base. Tnere is a wide prominence, hardly 

 to be called a tooth, within the outer lip in most examples, but in some 

 this is very low or wanting, and in none quite so prominent as in the 

 type of A. metamorphosa. Edentulous specimens resemble A. chirica- 

 huana closely, but they differ from that species by the slightly more 

 depressed shape, by having a rather deep, narrow gutter behind the 

 lip (almost wanting in A. chiricahuana) , by the smaller aperture 

 in shells of the same diameter, and by having the umbilicus wider 

 within, though not at its mouth. Three adults, No. 94,432, measure: 



Alt 8 7.3 6.7 mm. 



Diam 17 16.3 15 



Whorls 6£ 5| 6 



In 1906 we dug out a small series of dead shells (No. 97,930) from under 

 the snow and rocks in the head of Pine Canyon, 23 perhaps fifteen minutes 

 walk down from Barfoot Park. The callous "tooth" within the outer 

 lip is either weak or wanting in these examples, and four out of ten 

 adults taken show the weak trace of a parietal tooth. The most 



23 This canyon, which runs westward from Barfoot Park, is sometimes called 

 Riggs' Canyon, or Saw-mill Canyon. At its head a saw-mill stood, but it was 

 removed in the spring of 1907. 



8 



