INSECTS OF MOUNT RAINIER MELANDER. 421 



Mazama Ridge, like the lower ridge at Alta Vista, halts many 

 insects in their upward flight. At the very edge of the snow field, 

 the patches of bare volcanic sand are sufficiently warmed by the sun 

 to hold a little gathering of passers-by. Bee flies, " fleshflies," tiger 

 beetles, several species of large horseflies, and dainty little butter- 

 flies appropriate the sands as basking ground or dart back and forth 

 in the vicinity. One of the most beautiful of syrphus flies, Cali- 

 probola pulcher by name (pi. 8, fig. 7), is at home here, its metallic 

 bronze-green body reflecting the sunshine thus to catch the collector's 

 eye and to arouse his cupidity. It is interesting to note the proxim- 

 ity of strictly vernal forms and those of high summer at the edge 

 of the snow field. Nowhere at low elevations would it be possible to 

 find sawflies, mosquitoes, craneflies, and springtime empids cohabit- 

 ing with summer forms like robberflies, tachinids, bee flies, and long- 

 horn beetles. 



A short walk beyond the ridge, over the Paradise Glacier, brings 

 one to the edge overlooking the deep valley of the Cowlitz. Here 

 the slope is overgrown by the Indian basket grass which is the most 

 conspicuous of the alpine flowers. This plant is a species of lily, 

 with a hundred or so small creamy flowers crowning a tall, erect 

 stalk set in a dense mat of radiating narrow leaves. The flowers of 

 the basket grass are attractive to many insects but particularly to 

 the huge syrphid fly, Pocota grandis (pi. 9, fig. 3). It has been our 

 good fortune to see hundreds of these remarkable insects darting 

 from flower cluster to flower cluster, and even to catch them by the 

 camera as well as by the net. 



All of the insects that congregate on the ridges are not admired 

 by tourists, however, for mosquitoes likewise gather in disconcerting 

 numbers whenever the wind is not stirring. Naturally the marshy 

 flanks of the mountain afford excellent breeding places for mosqui- 

 toes, and at times these insects are decidedly in evidence, necessitat- 

 ing the wearing of a veil or the application of a perfumed oily 

 repellent for comfort. Fortunately, from our experience, the species 

 are strictly diurnal, so that when the cold air currents descend from 

 the ice dome at night mosquitoes do not trouble the camper's sleep. 

 Whenever one of the periodical storms sweeps over the mountain, 

 the frail mosquitoes are blown away, where we do not know or care, 

 but for days afterward there is a respite from their attacks, until a 

 new invasion emerges from the pools or comes up from below. 



Although conspicuous plant life ceases at the timber line, insects 

 occur still higher. Some of the species are indigenous, like the 

 wingless grasshoppers (pi. 9, fig. 2) and lubber crickets (pi. 9, fig. 6) 

 of the pumice fields. It seems remarkable that a plant-eating insect 

 like the dectiine cricket could occur so abundantly in a spot so bar- 

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