| Show Finds Parasite That Destroys BI Black ck Widows Widows' E Eggs s I May aY Control the Creature Spread of the black widow spider may soon be controlled by the laboratory laboratory laboratory labo labo- propagation of a rare and tiny parasitic fly that preys on the egg sac of ol the spider writes George Elwood Jenks In Nature Magazine The fly known to science as Gau- Gau rax was discovered in Los Angeles about 40 years ago alto but apparently apparently apparently ap ap- ap- ap was forgotten until Jenks rediscovered it in the spiders spider's egg sacs Nature has checks on the undue Increase of many creatures in the form of parasites and it is this minute fly By that controls the black widow Probably assisted by settlement however the black widow widow widow wid wid- ow has been increasing In numbers despite the activities of The spider spins her sac about the eggs she deposits and remains on guard throughout the Incubation period but It sometimes happens the parasite evades her watchful eyes and succeeds in laying its own eggs on the surface of the sac These eggs soon hatch and the tiny maggots provided with instinctive instinctive instinctive tive knowledge at birth at once bore through the tough walls of the egg sac to feast on the eggs within Jenks has experimented in an nn attempt attempt attempt at at- tempt to propagate this parasite and has bas succeeded in raising several thousand under artificial conditions The main problem at nt present is the preparation of a synthetic food for tor forthe forthe the larval flies that will substitute for the egg sacs of the spider When this problem Is s solved he believes it will be possible to propagate the parasites In by the milli million million mil mil- li lion n for tor widespread distribution and thus check the increase of the black widow |
