1913] Proceedings of the Cleveland Meeting 135 



prothorax of Hepialus was shown to represent the primitive arrangement 

 of setae and was used as a type for determining the homology of the seta) 

 on the different segments. The authors had studied many species and 

 gave figures of four: Hepialus lectus and H. humuH of the Jugatas, Pseu- 

 danaphora arcanella of the Tineidse and Mamestra picta of the NoctuidcE. 

 Each of these was compared with the type, segment for segment. This 

 is the first time the setas of the prothorax have been homologized with 

 those of the other segments. 



Discussion: W. A. Riley — I wish to speak in appreciation 

 of the important work which Mr, Tsou and Mr. Fracker have 

 reported upon — work which is especially difficult to present in a 

 non- technical manner. It is quite customary to ridicule work 

 upon such a subject as the "hair of a caterpillar" and even 

 some entomologists are inclined to question the possibility of 

 homologizing such structures. Yet, as Professor Comstock 

 sometimes says, "We read that the very hairs of our head are 

 numbered, and in the case of lepidopterous larvae this may 

 be literally true". That certain hairs or groups of hairs may 

 be persistent and may be homologized throughout a wide series 

 of forms, is due to the fact that they possess important sensory 

 functions. Pioneer work in this country on the homologizing 

 of setag was done by Dyer, and the late C. B. Simpson extended 

 this by an important study which is deposited as a thesis in the 

 Cornell University library. It is gratifying to see the work 

 continued under Dr. MacGillivray who is best qualified to 

 supervise it. 



Anna H. Morgan, ML Holyoke College: Eggs and Egg- 

 laying of May -flies. 



This study of May- fly eggs was made to determine the relative 

 fecundity of different species. This led to the study of a series of 

 elaborate sciilpturings found upon the chorion. In several species the 

 chorion bears long thread like extensions which tenninate in viscid 

 spheres or disks. These seem to help buoy up the eggs. Threads two 

 and three inches long were found. In nature these threads are probably 

 entangled in sticks and vegetation and this prevents the eggs from being 

 covered by silt. In the ovaries of half grown nymphs these structures 

 are well defined and are of aid in connecting up the life histories where 

 rearing is impossible. 



Discussion: Philip P. Calvert — It was remarked that Miss 

 Morgan's statements that Heptagenia inter punctella and H. 

 piilchella closely resembled each other as adults and lived in the 

 same situation as larvae and eggs might seem to indicate an 

 exception to Jordan's law that the nearest related species are 



