272 MR. w. scHAus ON NEW [Apr. 5, 



anatomically unisexual, yet functionally I believe it to be so. 

 Having observed numerous individuals and pairs, I am able to say 

 that the female is constantly larger than the male. 



I may add a word as to the best method of killing these moUusks. 

 If placed in a sort of vapour-bath or in a vessel of water, and heated 

 very slowly and gradually, they die painlessly and in a condition 

 with the tissues relaxed much more suitable for the purposes of the 

 anatomist than if killed by immersion in hot water or in any acrid 

 fluid. When it is desired to preserve the shell in a perfectly clean 

 condition, the whole should, after the animals are dead, be boiled so 

 that the soft parts may readily come away from the shell. 



4. Descriptious of new Species of Lepidoptera Heterocera 

 from Brazil^ Mexico, and Peru. — Part I. By W. Schaus, 

 F.Z.S. 



[Eeceived March 16, 1892.J 



The following descriptions are all taken from specimens iu my 

 own collection, and those of the Brazilian and Mexican species were 

 chiefly collected by myself. 



Fam. AgaristidjE. 

 Othria meridionalis, sp. nov. 



Velvety black ; the primaries with a narrow transverse band of a 

 creamy white, extending from the middle of the subcostal vein to 

 close to the inner angle. Underneath the transverse band is slightly 

 wider than on the upper surface. 



Expanse 34 mm. 



Hab, Petropohs, Brazil. 



Fam. Zyg^nid^. 



Harrisina janeira, sp. nov. 



Dull greenish black ; the second and third abdominal segments 

 bright red. 



Expanse 26 mm. 



Hab. Petropolis, Brazil. 



Harrisina dantasi, sp. nov. 



Dull black ; a bright orange spot on either side of the collar. 



Expanse 21 mm. 



Hab. Novo Friburgo, Brazil. 



Harrisina eminens, sp. nov. 



Bluish black ; the base of the wings yellow and on the primaries 

 a yellow mark crossing the wing fro'm the subcostal vein at about 

 two thirds from the base and extending to the outer margin just 

 above the inner angle ; this mark is somewhat in the shape of a T, 



