Popular Science Monthhj 



875 



T 



Great Fleas Have Little Fleas Upon 

 Their Backs to Bite 'Em" 



C^ the naturalist 



or to any one 

 accustomed to ob- 

 serve Nature closely, 

 tiie fact is apparent 

 that the problems of 

 ixistence are propor- 

 tionately the same in 

 c\"ery form or stratum 

 of life. Even the 

 common housefly, 

 which seemingly has 

 nothing else to do 

 but to crawl laziK- 

 over whatever is 

 left uncovered and 

 then go happily on 

 its way, doing its 

 best to bring about an 

 affiliation between tiie 

 clean and the unclean, 

 occasionally meets its 

 Nemesis in the form of a 

 tiny crab-like creature whicii 

 attaches itself to the fly's legs. 



These little creatures are known to 

 the scientist as pseudo-scorpions, or chelif- 

 ers. They may sometimes be found be- 

 tween the leaves of old books tliat ha^•e 

 stood unused for a long time, and also be- 

 neath the bark of trees and in mosses. 



Although they are called false scorpions 

 the\- resemlile the true scorpions ciosch- in 

 general structure cxcejit for their niimii;' 

 size. But they have no 

 poison gland as the 

 true scorpions have. 

 They attach them- 

 selves to otlier insects 

 also, but they seem to 

 be the special pest of 

 the houseflies. Scien- 

 tists suppose that 

 they seize the fly's leg 

 and hold on until the 

 fly dies, either worried 

 or frightened to death 

 by the undesirable pres- 

 ence. When the fly is 

 dead the little creature 

 feeds on the body. 



It is interesting to 

 watch them under the 

 microscope. A simple 

 hand-lens will show 

 them up to advantage. 

 They arc extremelv 



The tiny creature here seen un- 

 der the microscope literally makes 

 life an inferno for the housefly 



active, running sidewise and backwards and 

 gj'rating in curious and amusing ways. It 

 is easy lu imagine 

 the annoyance it 

 causes the fly, when 

 one or more of the 

 pests decide to join 

 hands with it; for 

 whatever other ac- 

 ti\ities the chelifer 

 may find it never 

 loses its hold of what 

 is to be its store- 

 iiouse of food" even- 

 tually. 



For, as De Mor- 

 gan says: 



"Great fleas have little 

 fleas upon their backs 

 to bite 'em; 



And little fleas have lesser 

 fleas, and so ad infinitum. 

 .And the great fleas them- 

 selves, in turn, ha\'e greater 

 fleas to go on; 

 While these again, have greater 

 till, and greater still, and so on." 



Iridescent Fish-Eggs for 

 Table Decoration 



PERSONS living on the Atlantic coast, 

 or visiting there during the summer, 

 often wonder at the beauty of the various 

 "berries" on seaweeds. Many a lo\er of 

 the seashore, and of the beautiful, has gath- 

 ered large quantities of these varie- 

 gated objects. They are beauti- 

 ful when artistically arranged 

 in a glass receptacle so as to 

 display the various colors, 

 but they are n(3t the fruit 

 of a marine plant. 



On the contrary they 

 are the eggs of the 

 eighteen-spine srulpin 

 and of other allied \a.- 

 rielies of sculpins, and 

 they furnish an excel- 

 lent example of the 

 astonishing profusion 

 of material with which 

 nature works along 

 certain lines in the 

 propagation of species. 

 She seems to realize 

 that many fish are fond 

 of these eggs and she 

 intends that there shall 

 be no diminution in the 

 number of sculpins. 

 She acts accordingly. 



The eggs of the eighteen-spine 

 sculpin arranged in a large jar- 

 diniere for decorative purposes 



