962 CHAKLES PAUL ALEXANDER 



Bengtsson (1897) erected for this genus the group Erucaeformia, which 

 he considered as the primitive form from which the Nematocera and the 

 Brachycera have been derived. This group, of course, has no standing 

 whatsoever. 



Phalacrocera replicata (Linn.) 



1761 Tipula replicata Linn. Fauna Suecica, 2d ed., p. 500-502. 



1863 Phalacrocera replicata Schin. Wien. Ent. Monatschr., vol. 7, p. 224. 



The larvae and the pupae of Phalacrocera replicata have been discussed 

 in such detail by Miall and Shelf ord, by Bengtsson, by Holmgren, and 

 by Wesenberg-Lund, that they are considered here only in general terms. 

 The habits of the immature stages have been discussed by many writers 

 since the time of De Geer. They are oftentimes rather numerous among 

 aquatic plants such as Ranunculus fluitans Lam., Fontinalis antipyretica 

 Linn., Hypnum elodes Schp., H. exannulatum Guenbel, and other species, 

 feeding on these mosses and probably on other plants. These moss frag- 

 ments give a green tinge to young larvae when seen thru the nearly trans- 

 parent body wall. Older larvae are more opaque and are brownish green 

 in color, indistinctly striped with pale and darker. The larva is extremely 

 sluggish, remaining almost motionless for hours. It clings to moss stems 

 by its large anal hooks, and, thus secured, it often sways its body from 

 side to side as if to accelerate respiration. The larvae can go for long 

 periods of time without fresh air. Miall and Shelford kept specimens 

 alive for two weeks in bottles completely filled with water, and for a 

 long time in water that had been boiled. The larvae can live for a long 

 time out of water. Progression thru the mats of submerged vegetation 

 is accomplished by grasping with the mandibles and the anal hooks, 

 alternately. When alarmed the larvae curl into a rounded ball, after 

 the manner of many caterpillars. The skin, and more especially the long 

 body processes, are often covered with ectoparasitic organisms, such 

 as algae and infusoria, on which small fresh-water mollusks, Plan- 

 orbis, have been observed feeding and creeping about over the body of 

 the larva. This coating of organisms, the body outgrowths, and the general 

 coloration of the larva, give it a striking resemblance to the mosses among 

 which it lives. De Geer (1776:355) shows that the larva can endure 

 excessive cold. He placed four larvae in a vessel at the beginning of 

 winter, and examined them in the following May. During the winter 



