200 Papers from the Department of Marine Biology. 



On June 17, following the 36 hours of calm, a light northeast wind 

 held until June 18, when it became north-northeast. During June 19 

 its direction was from the east. After a day's calm, on June 21, 

 a light breeze blew from the northeast, while that side of the dwelling 

 was being painted. Here a single insect was later found in the paint, 

 a strong-fljdng damsel-fly which may have come down the wind and 

 been able to make a landing, even though the air-current were sheering 

 off across the surface painted. 



An examination of the station on June 26 and 27 disclosed 6 living 

 and 1 dead house-flies, Musca domestica, in the lower rooms; one 

 mutilated damsel-fly and one pentatomid on the balcony beneath and 

 outside the lantern, and three dead gnats on the sills of the storm panes 

 inside. The gnats no doubt ascended from the dwelling below and 

 had been unable to find their way out. In addition to these which, 

 in all probability, reached the station by flight many larder pests 

 were discovered, including two species of moths, one breeding in stale 

 wheat flour and the other in packages of raisins, bean weevils (Bruchus 

 obtectus) in dried beans, and a heavy infestation of weevils in two cases 

 of the pilot bread which the keepers are required to keep on hand as 

 a provision against want during possible prolonged periods of inabilit}' 

 to secure their usual provisions from Key West. Each biscuit con- 

 tained upward of two dozen larvse and adults. 



Upon inquiry of the keepers it appeared that on June 19 "one or two 

 mosquitoes" had been observed by them in their living quarters, but 

 that this was a rare occurrence. The wind on the two preceding days 

 had been from the northeast and north-northeast, so that the source 

 may well have been the coast of Florida. It is probable that had a 

 careful lookout been kept at that time several other specimens would 

 have been noted. 



METHODS OF OBTAINING INSECTS WHICH VISITED THE STATION. 



On June 26 an insect net 5 feet in diameter and 6 feet deep was so 

 suspended from the balcony railing beneath the lantern that any wind 

 from the northeast, east, or southeast would spread it; but the hope that 

 insects might be caught in this net was not realized during the entire 

 period of observations. The lamp at this station is apparently not of 

 sufficient strength and its flashes not of sufficient length to attract 

 many of the insects which may be passing. During a revolution of the 

 lamp and lenses lasting 30 seconds two groups of three similar flashes 

 occur, each group requiring 9 seconds and being followed by a blank 

 interval of 6 seconds. 



Practically all mosquitoes and flies were taken with a hand net. In 

 order to catch all of the former a close examination of the entire station 

 was made several times a day in order to dislodge any which had found 

 resting-places in dark corners. However, most of the mosquitoes 



