186 Psyche [December 



reservoir enters the head. The malpighian tubes are forked dis- 

 tally for a considerable length, the forked and about half the 

 single portion being lobulate, the rest smooth. The color varies 

 from pale pink to dark purple-red. 



In the family Membracidse the alimentary canal (fig. 9) differs 

 in arrangement from the foregoing insects. The anterior part 

 of the reservoir only projects slightly into the thorax: posteriorly 

 it extends to near the extremity of the abdomen as a sac of large 

 diameter, though gradually narrowing to the reservoir-valve. 

 The posterior part of the oesophagus, together with portions of 

 the midgut and proximal parts of the malpighian tubes are wound 

 or twisted together, so that it is very difficult to disentangle 

 without injuring them, especially as their tissues where in contact 

 coalesce, and the whole mass or knot is invested by peritoneal 

 membrane. The malpighian tubes are forked, the fork extending 

 to somewhat near their point of origin. They originate 

 as two tubes, each of which afterwards forks and together form 

 the usual four tubes. The proximal single portions are smooth, 

 the rest lobulated. Often the mid-part of the tubes is much 

 swollen for a considerable length by urates, etc., and this portion 

 is then of an opaque white. Otherwise their color is pale brownish 

 or yellowish. The distal ends generally abut on the rectum, 

 into which they usually bulge somewhat. In other cases the 

 distal ends are sometimes united in pairs, but their lumina do 

 not communicate. 



Of the family Aleyrodidoe, Aleyrodes, sonchi Kotinsky, a native 

 of the Hawaiian islands (fig. 10), has no reservoir. The oesoph- 

 agus is very long and slender, and the posterior portion of it, 

 together with the anterior part of the hind intestine are twisted 

 around each other for some distance, and apparently enclosed 

 with a peritrophic membrane. The malpighian tubes are two 

 in number and very large; they appear to be always more or less 

 clear or hyaline and colorless. Besides uric acid there appeared 

 to be hippuric acid crystals in the tubes. The junction of the 

 midgut and hind intestine (where the malpighian tubes originate) 

 is right up at the anterior end of the abdomen, near the base of 

 the oesophagus, when the gut lies in its natural position in the ab- 

 domen. The tegimina and wings of this insect are white from 

 the wax excreted from the numberless tiny glands thereon. 



