OF WASHINGTON, VOLUME XV, 1913. 33 



One day last August (1912), Mr. Snyder remarked that a cer- 

 tain old chestnut log on Plummer's Island, Maryland, looked 

 right for them, and in a few minutes showed me a colony there. 

 Since then I also, have been able to find them, for these larvae 

 seem to occur in almost any old red-rotten or yellowish-brown 

 decaying oak or chestnut log, lying in the woods along the Potomac, 

 but the original capture by Hubbard and Schwarz, i.e. the occur- 

 rence in one colony of numerous larvae, pupa?, psedogenetic repro- 

 ductive form and winged adults ready for issuance, does not seem 

 to have been duplicated. 



My first suspicion that we were dealing with a really remarkable 

 case, came while looking at one of the vials of material that Mr. 

 Snyder wished identified. This contained three forms of larvae, 

 but the idea of identity was so improbable, that its expression 

 then would have seemed out of place. In addition to the normal 

 legless larva figured and described by Hubbard, there was a form 

 about one-half its length, similar in head and anal appendages 

 and furnished with long, slender, weak legs which are most remark- 

 able in the chitinized elongate tarsus, bearing two claws (see 

 plate III, fig. 2&). The third form was more robust than the 

 normal larva and seemed to be almost free from segmentation; 

 the whole body being soft and formless, the head indistinct, soft 

 and white, except the tips of the mandibles; the tail devoid of 

 the chitinous armature, but terminating in a blunt, transverse 

 carina. It was thought for a time, to be some obscure Dipterous 

 larva, but some resemblance in the contour of the head, and its 

 repeated occurrence with MicromaUhus larvae, suggested the possi- 

 bility of its being a prepupa. 



This hypothesis was shattered one afternoon at Plummer's 

 Island, when embryos began issueing alive, but in an oval shape, 

 from the ventral surface, close to the tip of the body of one that 

 had shortly before been isolated in a small vial. I watched two 

 issue, but my field lens was too weak, and more urgent work 

 pressing. Next morning there were seven young legged larvae 

 crawling about in the vial, while the mother was somewhat 

 shrunken and remained inactive. Lateral and ventral views of 

 this specimen are shown on plate III, figures 1, la. while figure 2 



of the pacdogenetic or sexed broods. Perhaps it may be merely a change 

 in temperature due to exposure of the log to sunshine, or food modified by 

 the growth of other organisms or ferments in the rotten wood. Mr. Schwarz 

 recalls that the original capture was in a large log in an open space in a 

 swamp and that the sun shone freely upon the log, while the adult reared 

 by Mr. Snyder was from a log on an open, sunny hillside. It seems impera- 

 tive that we secure the sexed adults, particularly the egg-laying female 

 amd determine if the young larva; hatching from her eggs are identical with 

 the young legged larvae here shown. 



