Dr. A. S. Packard on new North- American Phyllopoda. 337 



being full and rounded ; anterior dorsal edge slopes rapidly 

 from the unil><>iH's, and the anterior end is full and convex. 

 Umbones prominent and rather acute, but not oblique. About 

 24 lines of growth, between which the shell is coarsely punctate ; 

 from 5 to b dots (when placed in a straight line) between the 

 lines in the central part of the shell ; these punctures are reduced 

 to a single row on the edge. Length '30, breadth '23, thick- 

 ness "lo inch. 



It differs ixomE.im\cirana,C\-A\\?, (Grubc's figure) from Zima- 

 pan, Mexico, in the umbones being much more prominent, in 

 the prominent angle of the dorsal posterior edge, while there are 

 half as many lines of growth, t rom E. DunJceri, Baird, also 

 from Zimapan, it differs in the less numerous lines of growth, 

 in the smaller, less tumid umbones, and tiie more marked angle 

 of the posteri(^r part of the dorsal edge. The punctui'es between 

 the lines of growth are much more numerous in Dunheri. Six 

 specimens. Waco, Texas, April (G. W. Belfrage). 



Estheria Morsei, n. sp. — Shell intermediate in form between 

 E. CaldwcUi^ Baird, from Lake Winnepeg, and E. DunJceri^ 

 Baird, from Zima{)an, Mexico ; shell much swollen, oblong-oval, 

 of a pale horn-colour ; umbones large, prominent, larger than in 

 E. Ca/(/treUi, and much less oblique, and situated nearer tlie an- 

 terior end of the shell. Dorsal margin shorter than in E. Cald- 

 toelli, and in front of the umbones, instead of being straight and 

 suddenly curved downward, is regiUarly rounded as in E. 

 Dunheri. Behind the imibones the shell is naiTOwer than either 

 in Caldwelli or Dunkeri^ the dorsal edge sloping rapidly 

 downward, without the Avell-marked angle of Caldicelli or the 

 continuous fuU curve of Dunkeri. Coarse punctures between 

 the ribs, rather coarser than in Caldicelli, there being on an 

 average 5-10 between the ribs in the centre of the valve. 

 Length "oO, breadth "33, thickness '24 inch. Six specimens 

 from Dubuque, Iowa, collected by Rev. A. B. Kendig. Dedi- 

 cated to Prof E. S. Morse, who has indicated to me that the 

 species was undescribed. 



Lymnetis gracilicornis,n. sp. — This interesting form may at 

 once be known from L. Gouldt'i, Baird, recently found by Mr. 

 E. Burgess in Cambridge, Mass., by the long slender second 

 antennae, which have about 20 joints, and are much longer than 

 in that species. The keel on the front of the head does not 

 reach to the front edge, while in Gouldii it does. Shell of the 

 same form but much larger than in Gouldii. Length of shell 

 •17, breadth '16 inch. Texas (Belfrage). 



Peabody Academy of Science, Salem, Mass., May 20, 1871. 



