REPORT OF THE STATE ENTOMOLOGIST I91O 83 



of diverging antennae and quite different from the strongly convex, 

 usually fuscous head of Sciara larvae sometimes occurring in similar 

 situations. Predaceous larvae likely to be associated with Miastor, 

 may be instantly recognized by the body tapering to the small 

 anterior segments, and especially by the chitinized, usually fuscous, 

 hooked mouth-parts. Small Dipterous maggots having a length 

 of one-twentieth to one-eighth of an inch and occurring under con- 

 ditions described above, should be carefully examined if one is 

 searching for this or allied species. 



Value to zoologists and biologists. Miastor larvae and their 

 allies should be of great service to teachers of zoology and biology, 

 since they admit of the study at first-hand of one form of partheno- 

 genesis. It is possible with a no more elaborate outfit than an ordi- 

 nary student's microscope equipped with a three-quarter objective, 

 a microscopic slide and a few cover glasses, to observe the vital 

 activities of the young larva, to see the muscular, respiratory, 

 digestive and nervous systems, to identify the ovaries and to 

 watch the gradual development of the semitransparent embryos 

 w^ithin the mother larva. Furthermore, this larva is well adapted to 

 more exact histological methods, being soft and therefore an excel- 

 lent subject for serial sections and stains, particularly as it is com- 

 paratively easy to secure from one colony a series of individuals 

 representing different stages of development. 



There are other considerations aside from the interest attaching 

 to their morphology and biology which should appeal strongly to the 

 teacher of zoology. These larvae are widely distributed and, with 

 an understanding of their habits, there should be little difficulty in 

 finding them. Moreover, they are small, and a piece of wood six 

 inches long, three inches wide and half an inch thick may contain 

 or produce material enough for a fair sized section or class in 

 zoology. The larvae are prolific and under favorable conditions 

 would probably multiply at any season of the year. This is cer- 

 tainly true of the fall, the early winter and the spring. They are 

 so amenable to artificial conditions as to make it possible to keep 

 them alive for at least a month in microscopic cells, and with care 

 a larval generation will develop in such restricted quarters. We 

 have kept larvae healthy and multiplying for more than three 

 months with nothing more elaborate than a moist piece of decaying 

 wood clamped lightly to an ordinary microscopic slide. These 

 remarkable larvae are very hardy. Prolonged dryness simply results 

 in a suspension of activities, while they are quite resistant to an 



