122 PROCEEDINGS ENTOMOLOGICAL SOCIETY 



myriopods in such a small area as a square foot. Several attempts 

 at such a count gave the impression that there were from fifty to 

 one hundred individuals per square foot. All were travelling 

 in the same general direction westward but their ranks were 

 denser in places and towards the edges of the army there seemed 

 to be more or less distinct columns. Specimens taken for the 

 National Collection were of a pale color, less than an inch in 

 length and looked like half grown individuals of our eastern 

 F ontaria, but have never been determined. 



About two weeks after the observation just described the writer 

 saw quantities of what he supposed to be the same species lying 

 dead at the foot of an exposed vertical bank near where the 

 Hoopa Trail crosses Redwood Creek at Bair's Ranch, perhaps 

 25 miles east of Fieldbrook and not in the Redwood Belt. He 

 believes this mortality could be explained by supposing that part 

 of an army similar to that just described was crossing the face 

 of this bank when the early morning sunlight overcame them 

 and killed those which rolled to the bottom where there was no 

 shelter from the sun. In the same way he had seen other unpig- 

 mented inhabitants of the peaty soil of the dark forests such as 

 small myriopods, springtails, and even pale, blind beetles stim- 

 ulated to violent activity ending in a few moments in death, 

 while he was sifting in the bright sunshine. 



Mr. Banks has kindly referred the writer to the paper by 

 Bollman 1888 (Ent. Amer. vol. 4. p. 3) where Fontaria virginiensis 

 Drury is reported to have been found crawling on the surface of 

 the ground in large numbers at Donaldson, Ark., July 11, 1887, 

 there being perhaps one adult among five or eight hundred young. 

 The only other accounts of such mass migrations of myriopods 

 known to the writer are contained in letters from Mr. Fred E. 

 Brooks, dated July 13 and August 6, 1908, transmitting specimens 

 of Fontaria brunnea from Weston, West Virginia, to the Bureau 

 of Entomology, and stating that they evidently emigrated from 

 the woods, and, moving in armies, invaded dwelling houses and 

 outbuildings, fell into springs and wells and in some cases died in 

 such numbers as to emit a strong stench. In one case the walls 

 of a cellar where they congregated were washed down with hot 

 water several times during their four days' visit at that place and 

 each time two or three gallons of myriopods were taken out. 

 Perhaps a dozen such armies in that section of West Virginia had 

 at that time been reported to Mr. Brooks, who has just replied 

 to a recent inquiry, as follows: "Since writing the letters referred 

 to by you, I have observed migrating armies of the myriopods 

 several times but never in so great numbers as were observed 

 at Weston in 1908. Almost every year 1 hear of such armies 



