SPONGILLA-FLIES — PARFIN AND GURNEY 429 



star larva is ready to pupate, it crawls to some object upon which 

 i may emerge from the water. It may wander for several hours 

 {ter leaving the water, occasionally as far as 50 feet or as high as 

 ] feet, before spinning its cocoon on an appropriate substrate. 

 ];own (1952, p. 149) noted that from about four to eight hours elapsed 

 l)m the time areolaris left the water until it finished its spinning. It 

 sent from 30 to 60 hours in the cocoon as a prepupa before pupating. 

 Jeedham (1901, p. 556) observed that two larvae of vicaria 

 \-umhrata) spent at least 12 hours in spinning their cocoons and 

 imained prepupae ("inactive larvae") for 24 hours before pupating, 

 'syrid cocoons have been recorded on the bark of trees (crevices), 

 bat hulls, spiderwebs, grass blades and stems, Scirpus culms, pine 

 nedles, docks, bridges, woodpiles, undersides of stones above water, 

 j)ers of hemp rope, corpses or exuviae of other insects (as those of 

 cagonfly naiads and mayfly subimagines) , and sometimes adjacent 

 ' gyrinid cocoons. 



The cocoons of Sisyra vicaria and the majority of those of Climacia 

 ieolaris examined appeared similar and almost single-layered in 

 ;iucture, with the double layer difiicult to discern (pi. 3, fig. 6). On 

 le surface of the cocoon may be seen coarse, widely spaced, irregular 

 'rands of silk, almost interwoven into the cocoon itself. The strands 

 ■e frequently pale greenish on the specimens of vicaria and yellowish 

 1 those of areolaris examined ; and yellowish on fuscata and terminalis 

 (COons, according to Withycombe (1923, p. 523). 

 i Of 19 specimens of areolaris, with cocoons from which they emerged 

 dndly sent by Dr. Hungerford), only three made cocoons which 

 lowed the artistic, loose, hemispherical outer net of a widely spaced 

 jxagonal mesh and the whitish inner cocoon of finer, more compact 

 sxture attributed to this species {=dictyona) by Needham (1901, 

 p. 559, 560, pi. 12) (pi. 3, fig. 7). The specimens were collected by 



ungerford in Cheboygan County, Mich., from July 22 to 26. The 

 3 specimens without the outer net appear slightly broader, with 

 )unded ends, and more whitish than the vicaria cocoons, which are 

 ipered slightly at one end; however, it is realized that type of sub- 

 jate and age may have some effect on the shape and color of the 

 )coons. A cocoon oi fuscata from Holland possessed an outer open 

 et similar to but with smaller and less regularly hexagonal spaces 

 lan those of areolaris. It is slightly yellowish. The inner cocoon 



white, parchmentlike and oval. Kiilington (1936, pi. 4, fig. 3) 

 lowed a photograph of a cocoon of a European specimen oi fuscata 

 ith a similar outer net. 



Brown (1952, p. 148) has pointed out that when the areolaris larva 

 tiooses a cocoon site lacking an adequate substrate (as grass blades 

 ad stems, etc.), or sometimes when the substrate is adequate, the 



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