690 



SCIENCE 



[N. S. Vol. XXXIV. No. 881 



aerological work has been extended so that it 

 is now carried on daily, including Sundays. 

 Another innovation at Mount Weather is that 

 of obtaining wind velocity aloft. The series 

 of nine soundings of the free air made in two 

 days is probably unprecedented in the annals 

 of meteorology. This occurred on September 

 12 and 13 last, when from 6 :37 in the morning 

 of the first day to 1 :06 in the afternoon of the 

 next day the nine kite flights were made one 

 after another, without a pause between them. 

 During the last of these flights a west-north- 

 west wind with a velocity of 69 miles per hour 

 was successfully navigated by a kite at a 

 height of 10,1YY feet above sea level. 



The " spectre of the Brocken " is a phenom- 

 enon usually observed only from mountain 

 summits. But for two hours on the night of 

 August 6 it was observed by the writer from 

 the top of the Blue Hill Observatory tower, the 

 height being about YOO feet above sea level. 

 Fog, which had been brought in from Boston 

 Harbor by a light easterly wind, arrived at 

 Blue Hill shortly before eight o'clock. Its 

 upper surface, which was very distinct, was 

 about at the level of the upper windows of the 

 tower. The moon, about three-quarters full, 

 was well above the horizon, and a few scattered 

 cirrus streamers were the only high clouds 

 visible. From the top of the ladder on the 

 anemometer poles the surface of the fog 

 stratum had the appearance of a wavy sheet of 

 water. Directly opposite to the moon the 

 observer could see, at an estimated distance of 

 Y5 feet, a dark image of himself enlarged about 

 three times his natural size. The image was 

 surrounded by a white light which faded away 

 at its edges, leaving a dark space between it 

 and a broad colorless circle, sometimes called 

 "IJlloa circle" or "white rainbow." The 

 circle was complete and appeared to have a 

 radius of about 22°. When the observer 

 moved the whole apparition moved likewise, 

 proving it to be an entirely subjective phe- 

 nomenon. It disappeared later when the fog 

 deepened, rendering the moon invisible. 



Andrew H. Palmer 



Blue Hill Obsbevatobt, 

 November 1, 1911 



SPECIAL AMTICLES 



THE LITE HISTORY OF A PARASITIC NEMATODE 



HABRONEMA MUSC^ 



Fifty years ago, from Bombay, India, the 

 late H. J. Carter* reported the discovery of 

 nematodes parasitic in the house fly, giving 

 them the name of Filaria muscw, and suggest- 

 ing that their investigation might throw light 

 on the life history of the guinea-worm. In 

 the same year Diesing ^ transferred Carter's 

 species to the genus Hahronema, making it 

 the type. Carter's description and figures, 

 though not accurate in all respects, particu- 

 larly in the interpretation placed on certain 

 details of structure, are sufficient for the recog- 

 nition of the species. Subsequently to Carter, 

 several writers have mentioned the presence of 

 nematodes in the house fly, in some cases iden- 

 tifying them with Carter's species, in other 

 cases being apparently unaware that the spe- 

 cies had ever been described or named. Leidy ' 

 noted the occurrence of Habronema muscoe in 

 about 20 per cent, of flies examined at Phila- 

 delphia. Further than occasional records of 

 the occurrence of Habronema muscoe in flies, 

 practically nothing up to the present time has 

 been added to Carter's account of the worm, 

 though it has long since become known that 

 this parasite has nothing to do with the 

 guinea-worm. 



In the summer of 1910, the present writer 

 found Habronema muscce fairly common in 

 house flies caught at Washington, D. C. The 

 fact that this nematode occurred in the larval 

 stage in flies suggested two alternative hy- 

 potheses, first, that the adult was a free living 

 form, second, that the adult occurred para- 

 sitic in some host other than the fly. No 

 evidence favoring the first hypothesis was ob- 

 tained, as the nematodes from flies when 

 placed in various media such as water, damp 



^Ann. and Mag. Nat. Hist., Land., 3 s. (37), 

 V. 7, January, 1861, pp. 29-33, pi. lA, Figs. 1-4. 



' Sitzungsb. d. 7c. ATcad. d. Wissensch., Wien, 

 Math.-naturw. CI., v. 43, 1 Abt. (4), pp. 273-274, 

 1861. 



'Proc. Acad. Nat. Sc. FMU. [v. 26, 3 s., v. 4] 

 (2), April-September, 1874, pp. 139-140. 



