442 ENTOMOLOGICAL NEWS. [DeC, '15 



larvae of Argia moesta putrida (dimensions as before: 7.5, 3 

 and 4 mm., and smaller), from the vicinity of Philadelphia, 

 showed that a larva watched for two hours may give no sign 

 of rhythmic rectal contractions, but that these may suddenly 

 begin and then continue for varying periods. They con- 

 sisted of sets of three rapidly successive contractions, every 

 third contraction being of longer duration than the other two ; 

 32 such sets per minute were noted. At other times sets of 

 five contractions were noted. In some larvae, but not in all, 

 the beginning of a set of rectal contractions was often syn- 

 chronous with a slight shortening of the abdomen ; the length- 

 ening of the abdomen began before the contractions had ended. 

 A rhythmic shortening and lengthening of the abdomen may 

 perhaps furnish an indication of the existence of rectal con- 

 tractions in opaque larvae. Successive removal of the three 

 caudal gills in one larva was not followed by any immediate 

 beginning of rectal contractions, although such were seen four 

 hours later ; the larva was not under continuous observation 

 during all of that time, however. The observations of the 

 Argia larvae were made chiefly under a Zeiss compound mi- 

 croscope, objective A, ocular 2. 



Lateral External Abdominal Tracheal Gills 



are now known for the following Calopteryginae :* 



Euphaea splendens. Hagen, C. R. Soc. Ent. Belg, xxiii, p. Ixvi, 

 1880; Zool. Anz. iii, pp. 160, 304, 1880.t Packard, Text-Book Ent. 

 pp. 468-9, fig. 446, 1898. 



Euphaea variegata. Ris, Tijdschr. Ent. Iv, p. 168, pi. 6, figs. 9, 

 15-20, pi. 7, figs. 10-12, pi. 8, figs. 13, 14, 1912. 



*The references are to descriptions of the larvae only. 



fHagen states (/. c. p. 160) : "Die ersten derartigen Larven erhielt 

 ich von Nietner in Ceylon und habe iiber sie miindlich in der Naturf.- 

 Versamml. in Stettin 1861 berichtet." The Versammlung der deutscher 

 Naturforscher und Aerzte in Stettin was in 1863, not 1861. The 

 Bericht of that [38th] Versammlung for September 23, 1863, p. 137, 

 reads "Herr Dr. Hagen. iiber Respirations-Organe von Euphaea splen- 

 dens, woran sich eine Discussion schloss, an der sich besonders Di- 

 rector Loew und Prof. Grube betheiligten," but nothing more. The 

 Versammlung of 1861 was at Speyer and the Bericht thereof con- 

 tains nothing by Hagen and nothing on Buphaea. 



