•- 



41 



to adopt in order to prevent the repetition of synonyms. The name 

 " aquations" certainly docs not apply to the habits of the animal ; 

 but that of M Canadensis" is equally unfortunate, as it is more com- 

 mon in the Southern States than in Canada. 



S. Townsendi, Bach. Dental formula incisors \ ; false molars g ; 

 true molars \ = 44. Length of the head and body 7 inches 6 lines ; 

 of the tail one inch 6 lines ; breadth of the palm 6 lines. Body thick 

 and cylindrical, shaped like S. aquaticus, but larger. The whole up- 

 per and under surface is of a dark color, in most lights appearing 

 black ; the hair, when blown aside, exhibits a greyish black color, 

 from the roots to near the tips. The tail is slightly clothed with 

 short, strong bristles. Brought from the banks of Columbia river. 



S. Breweri, Bach. Glossy, cinereous black above, brownish 

 beneath. Palms narrow. Tail flat, broad and hairy. Dental for- 

 mula — incisors \ ; false molars }* ; true molars \ ; = 44. Length 

 of the head and body 5 inches 11 lines; of the tail 1 inch 5 lines ; 

 breadth of the tail 4 lines ; of the palm 4 lines ; length of the palm 

 to the end of the middle claw 7 lines. Its most striking peculi- 

 arity is its tail, which, instead of being round and nearly naked, 

 as in S. aquaticus, is flat and broad, resembling, in some respects, 

 that of the Beaver, and is very thickly clothed, above and beneath, 

 with long stiff hairs, which extend 5 lines beyond the vertebrae. 

 Found at Martha's Vineyard. 



S. latimanus, Bach. Broad-palmed shrew-mole, larger than the 

 common shrew-mole, intermediate in size between S. Townsendi 

 and S. Breweri. Hair longer and thinner than in either of the 

 other species, and slightly curled. Palms larger than in any of the 

 known species. Color nearly black. Tail naked. Length to the 

 root of the tail 7 inches 7 lines ; of the tail 10 lines ; breadth of the 

 palm 10 lines ; of the tarsus 7 lines. Mexico and Texas. 



Dr. Storer also read part of a " Monograph on the Arane- 

 ides of the United States," accompanied with Plates by 

 Prof. N. M. Hentz, of Florence, Al. The following spe- 

 cies of the genus Mygale, are described : 



M. truncata. I iceous ; cephalothorax with .< c | sion 



behind the middle, cheliceres terminated by several points above 

 the fang, hairy; abdomen cylindrical, suddenly truncated at the 

 end, and callous at that place, with concentric grooves and 6 cir- 



6 



