XXXJi, '21] ICXT'iMo] OOICAL XKWS 263 



In brief, the principal points here brought out are as follows : 

 The paraprocts, pr, or parapodial plates which bear the cerci 

 in the insects shown in Plate V, Figs. 1, 2, 3, 4, 6, 8, 9, 11, 12 

 and 13 represent the protopodites, pr, or basal plates of the 

 uropods of the Crustacea, shown in Figs. 16, 15, 14, 10, 7, and 

 5. The cerci (en of Figs. 1. 2, 3. 4, 6. 8, 9, 11, 12 and 13) of 

 insects represent the endopodites of the uropods of Crustacea 

 ( ;'. e., en of Figs. 16, 15, 14, 10, 7, and 5). and the "parapro- 

 cessi" of certain insects (r.r of Figs. 11 and 12) or the lateral 

 caudal gills of certain immature Odonata (>.r of Fig. 9) 

 represent the exopodites of crustacean uropods ( /'. e., the struc- 

 tures labeled c.r in Figs. 16, 15, 14, and 7). The eleventh 

 tergite, cp, of Figs. 8, 9, 2, etc., may bear an appendage in the 

 form of a median process (tf of Fig. 8), or a median gill (tf 

 of Fig. 9), or a terminal filament such as the "telofilum" labeled 

 fif in Figs. 2, 3, and 6. It is possible that this telofilum may 

 correspond to the terminal spine of merostomes, etc., but I have 

 not yet determined this point. 



ABBREVIATIONS 



The arable numerals denote the number of the abdominal segments. 

 bv.... Basal plate of ventral valvulae of ovipositor. 

 dr. . . .Dorsal valvulae of ovipositor. 



en Endopodite of crustacean uropods; cerci of insects. 



f/>. .. .Terminal tergite of Crustacea; epiproct, or eleventh tergite <>! 



insects. 



ex Exopodite of crustacean uropods; paraprocessus of insects. 



// Fractilinea, or line of breakage. 



ha . . . .Hypandrium, or sternite beneath male genitalia. 



it- Inner valvulae of ovipositor. 



/'c.... Penis. 



/>;-.. . . Protopodite of crustacean uropods; paraprocts of insects. 



,s- Styli. 



tf Telofilum, or terminal filament of Apterygota and Ephemerida ; 



telappendix or dorsal appendage of "larval" dragonfly ; median 



caudal gill of "larval" damselfly. 

 : r. ... Ventral valvular of ovipositor. (Dorsal valve in Fig. 2.) 



