452 ENTOMOLOGICAL NSWS. [DeC, 'll 



Rudiments of the superior appendages or 'cercoids' of the imago 

 viewed dorsally half as long, or less than half as long, as lo, digitate, 

 bent more or less ventrad near the middle of their length in the male, 

 nearly straight in the female, pale brownish-yellow. (PI. XVII, Fig. 

 8, sa). 



The three caudal gills much darker in color than the abdomen, 

 lozenge-shaped or diamond-shaped in transverse section of the an- 

 terior portion or stalk (which comprises one-half to three-fifths of 

 the total length of the gill), the vertical diameter greater than the 

 horizontal, the four angles distinctly keeled or carinate, the carinas 

 minutely serrate (less marked on the lateral carinse of the median gill 

 and on the mesial carina of each lateral gill), each serration bearing 

 a short hair; on the two lateral gills the dorsal serrations are larger 

 and fewer than the ventral serrations, while on the median gill the 

 dorsal serrations are smaller and more numerous than the serrations 

 of the ventral edge. The height of each gill (i. c, its vertical diam- 

 eter) increases gradually from the base caudad to one-half or three- 

 fifths of the total length and then expands more abruptly into the 

 thinner, foliaceous. terminal portion (PL XVII Figs. 12, 13, PI. XVIII, 

 Fig. 10), which may taper rather rapidly to an acute apex or may 

 end as a fully rounded convexity. The lateral carinae of the anterior 

 stalk of the gill are not continued on to the terminal foliaceous por- 

 tion, but the dorsal and ventral carinae are continuous with the non- 

 serrated but sparsely hairy dorsal and ventral edges of the foliaceous 

 part. The maximum height of the foliaceous part is about twice th^ 

 maximum height of the stalk. The caudal gills are held in life so that 

 the foliaceous part is vertical (PI. XVIII, Fig. 11). 



The following viscera are described from larva No. i, the only one 

 which has been dissected as yet. 



The fore-gut reaches to the middle of the third abdominal segment, 

 the mid-gut to the anterior end of the seventh abdominal segment 

 (PI. XVII, Fig. 8). The distinct gizzard is armed with eight larger 

 and eight smaller longitudinal chitinous folds, all bearing teeth (PI. 



XVTI, Fig. 9), whose fornuila mav be written 8 ( F V , f " I 



\ 6'-io'^ 2' / 



(cf. Higgins, 1901. pages 132, 133. 136.) 



The rectum opened longitudinally and spread flat has three wider 

 cellular (glandular?) longitudinal areas, one of which is mid-dorsal, 

 the other two right-ventral and left-ventral respectively, separated by 

 narrower, non-cellular, longitudinal bands (PI. XVII, Fig. lo). The 

 ■nuclei of the cellular areas can be seen in the unstained rectum, but 

 become much more distinct after staining (alum carmine was em- 

 ployed). Each of these three cellular areas is supplied with a branch- 

 ing trachea which for the ventral areas is a derivative, direct or in- 

 direct, of the lateral trachea of the same side of the body (PI. XVII, 



