Fresh water, Florida, South Carolina, Lake Erie, Lake 

 Michigan. 



Subfamily Palaemoninse. 



(Including the genera Leander Desmarest, Palcemon 



(pars Fabr.) Stimpson, Hymenocera Latreille, and Cry- 



jphiops Dana; which have the second pair of thoracic feet 



larger than the first, the carpus never annulate, and the 



mandible with a palpus.) 



Genus LEANDER Desmorest. 



89. Leander tenuicornis Smith (in letter), Palcemon tenuicor- 

 nis Say, Jour. Acad. Nat. Sci., Philadelphia, 1818, i, p. 249. Palcemon 

 natator Edwards, Hist. Nat. des Crust., 1837, ii, p. 393. Goodsir, Ann. 

 and Mag. Nat. Hist., 18-15, II, xv, p. 74, pi. VII, f. 3. Dana, U. S. 

 Expl. Ex. Crust., 1852, i, p. 588, pi. XXXVIII, f. 11. Palcemon tenui- 

 rostris Edw., op. cit., p. 395. Leander erraticus Desmarest, Anuales 

 Entomolog. Soc. de France, 1849, vii, p. 87. Leander natator Stimpson, 

 Proc. Acad. Nat. Sci. Phila., 1860, p. 40. 



Gulf weed, Atlantic. 



90. Leander pandaliformis Stimpson, Annals N. Y. Lye, 1871, 

 X, p. 130. 



AVest Indies. 



91. Leander gracilis Smith, 2nd and 3rd Report Peab. Acad. 

 Sci., 1871, p. 97. 



West coast Nicaragua. 



Genus PAL2EMON Fabricius, Stimpson. 



In the Proceedings of the Zoological Society of Lon- 

 don, 1868, p. 363, Mr. C. Spence Bate proposed a new 

 genus (Macrobrachium) for certain Palcemoiis, in which 

 the second pair of thoracic feet are enormously developed, 

 but here, as in most cases where comparative measure- 

 ments are made the basis of division, the various forms 

 intergrade so that the separation cannot be made. Mr. 



