130 THE NAUTILUS. 



females were present. The same was the case in specimens 

 from Big Deceiper Creek, Gum Springs, Clark County, collected 

 September 25, 1911. Of two gravid females collected in Mal- 

 vern Creek, Malvern, Hot Springs County, June 10, 1912, one 

 had eggs, the other glochidia. Another female, collected August 

 9, 1912, by A. A. Hinkley in Big Creek, Solitude, Posey County, 

 Indiana, was gravid with eggs. As will be remembered, I 

 found myself gravid females with eggs in Pennsylvania on June 

 17, 1909. 



Thus eggs are known to occur on June 10, June 17 and Au- 

 gust 9, while glochidia were present on May 19, June 10 and 

 June 26. These records are rather confusing. It may be that 

 the beginning of the breeding season is irregular (June to Au- 

 gust), and that the glochidia are discharged in June, so that the 

 end and beginning of the season overlap. But this should be 

 studied more closely. 



In the female the inner mantle- edge in front of the branchial 

 has the following structure: First, immediately in front of the 

 branchial, there is a group of four to six small papillae with 

 black base and whitish tips; then follows a slightly lamellar 

 expansion of the inner edge, which is right in front of those 

 papillae thickened, so as to form the "caruncle." This carun- 

 cle may be white or brownish (chestnut), of various shapes, 

 cylindro-conical, or pyramidal, or semi-globular, sometimes 

 somewhat divided. In front of the caruncle the edge is slightly 

 wavy and disappears soon. The group of small papillae, with 

 their black base, form a more or less marked black spot, and 

 sometimes this black color extends forward and backward, for- 

 ward so as to enclose the base of the caruncle, backward along 

 the base of the papillae of the branchial. Also in the male the 

 group of small papillae is present and marked by a black spot, 

 and in front of this the inner edge is slightly lamellar, but 

 without a caruncle. 



In most of the specimens recently investigated, the supraanal 

 opening was not closed, but normal, separated from the anal 

 by a mantle connection a little shorter than the supraanal, but 

 as long as or slightly longer than the anal. But in one speci- 

 men from Malvern, a male, the supraanal is undoubtedly 



