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leaf stalks of our common yellow pond lily {NupJiar Advcnd) at 

 Ithaca, N. Y., which I believe to be ^. Melanopyga. These I 

 have now under observation in aquaria in my laboratory. And 

 I hope ere long to be able to give a detailed account of them. I 

 will now briefly record a few of the more interesting points 

 already observed. 



The larva is furnished with nine pairs of spiracles, each of 

 which, excepting the ninth, occupies the usual position. The 

 ventro-dorsal diameter of the last segment is much less than that 

 of the remainder of the body, this segment appearing as if the 

 dorsal half had been cut away. The spiracles of the penultimate 

 segment are situated in the dorsal part of the posterior end of the 

 segment ; which, on account of the peculiar shape of the last 

 segment, is free. These spiracles are much larger than the others, 

 and are doubtless the ones chiefly used while the larva is in its 

 burrow. The position and direction of these spiracles remind us 

 of the arrangement of the respiratory system in many Dipterous 

 larvae, which live either in water or masses of decaying matter. 

 Frequently these lily-borers remain with only the caudal tip of 

 the body projecting from the water, evidently using the posterior 

 spiracles as just indicated. They can, however, descend below 

 the surface of the water and remain there a long time. My ob- 

 servations on this point are limited, but I have seen a larva re- 

 main entirely underwater voluntarily for the space of a half hour. 

 The tracheae of these larvae are unusually large. May they not 

 serve as reservoirs of air for the use of the insect while under 

 water ? 



These larvae are able to pass on the surface of the water from 

 one leaf to another. This they do with a motion similar to that 

 of a water snake. 



Associated with the larvae oi A. Melanopyga in Florida, I found 

 another Lepidopterous larva, a somewhat smaller insect, living 

 more upon the surface of the leaf. This species I failed to rear 

 to the adult state. 



The following is Mr. Grote's description : 



Arzama melanopyga, n. s. 



? . Allied to Viibiifica, with very similar markings and color,, 

 but the thick anal tuft of the female is discolorous and black or 

 blackish. Front unarmed, smooth. This character separates 

 SpJiida Obliqiiata ixova Arzama Diffusa, Vitlnijica ^.nd Melanopyga. 

 According to Mr. Butler, who has kindly examined Mr. Walker's 

 type o{ A7-zania Densa from Georgia in the British Museum, the 

 type of the genus agrees in having the front smooth. The two 

 genera are allied, but the characters of the clypeus are decidedly 

 of generic value in the moths ; upon these several genera are 

 founded, and we can thus separate Ochria (Gortyna Lcci^ and 

 Gortyna (Hydroecia Led.). Both Arzavia and SpJiida are internal 

 feeders ; the chrysalids of Obliqiiata have been taken in stumps 



