308 



SCIENCE 



[N. S. Vol. XXXVII. No. 947 



by the fact that the cross vein r-m is in direct 

 line with the distal part of J?n, making the latter 

 appear to arise from M. It is suggested that the 

 same interpretation should be made in the case of 

 the Molannidas and the Leptoceridse. In these 

 families Ei has more definitely assumed relations 

 with M, with which vein its distal part may be 

 wholly fused. This interpretation is based not 

 only on comparison with Helicopsyche, but also 

 upon the fact that it leaves the "corneous point" 

 within cell Et, where it occurs in all other families 

 if it occurs at all. The venation of the hind wings 

 of these forms is similarly interpreted. 

 Lucy W. Smith, Mt. Holyoke College: Mating 



and Egg-laying Habits of Perla immarginata. 



In introduction the paper gives a general de- 

 scription of the method of keeping adult stoneflies 

 under observation in captivity, and of handling 

 their eggs. This is followed by a detailed account 

 of the genital armature, copulation and egg-laying 

 habits of a single species, Perla immarginata. 

 Alvah Peterson, University of Illinois: Head 



and Mouth Parts of Cephalothrips yuccw. 



A preliminary report on the asymmetry of the 

 mouth-parts of Thysanoptera. A detailed descrip- 

 tion of the anatomy of the mouth-parts and head 

 capsule of Cephalothrips yuccw, a species belong- 

 ing to the suborder Tubulifera, was given. Nu- 

 merous details and parts heretofore undescribed 

 as to mandibles, hypopharynx, epipharynx, arms 

 of tentorium, etc., were shown. Similar observa- 

 tions were made on Anthothrips veriasci in order 

 to verify results found in Cephalothrips yuccw. 



Comparing the work done by H. Carman on 

 Limothrips cerealium, a species of Terebrantia, 

 with the work done by Muir and Kershaw on a 

 species of Tubulifera, a difference in interpreta- 

 tion exists as to whether the asymmetrical parts 

 are mandibles or maxilla?. Muir and Kershaw 

 interpret the asymmetrical parts as maxillfe. 

 Observations made by the writer on two species 

 of Tubulifera verifies their position in general. 

 The writer expects to continue his observations on 

 species of the suborder of Terebrantia to deter- 

 mine if possible whether the interpretation of H. 

 Carman is correct or not. 

 J. E. WODSEDALEK, University of Wisconsin: Life 



History and Habits of Trogoderma tarsale, a 



Museum Pest. Read by title. 

 Leonard Haseman, University of Missouri; Life 



Cycle and Development of the Tarnished Plant 



Bug, Lygus pratensis Linn. Presented by the 



secretary. 



Owing to the very serious injury to peach and 

 pear in the early spring which seemed to be due 

 to the work of the tarnished plant-bug, the writer 

 has undertaken a careful study of the life cycle, 

 habits and development of this insect. The work 

 has been carried through the late summer and fall 

 months and will be continued throughout the fol- 

 lowing spring and summer. 



In this work it has been found that the tar- 

 nished plant-bug breeds largely upon various 

 flowering weeds, such as wild asters, daisies and 

 mare's tail (Erigeron canadensis). The tarnished 

 plant-bug deposits its eggs in the blossoms of the 

 host plant and not in the tissue of the leaves or 

 stems. These eggs hatch in from five to seven 

 days and the insect passes through five distinct 

 nymphal stages in its development in the place of 

 four, as other writers have maintained. The insect 

 remains in each nymphal stage for about the same 

 length of time and completes its growth in from 

 thirty to thirty-five days. 



Victor E. Shelfokd, University of Chicago: The 

 Ontogomy of Elytral Pigmentation in Cicindela. 

 The pigment develops in the form of a faint 

 pattern, somewhat variable, but with certain 

 lighter areas occurring in the same general posi- 

 tion in several species. These lighter areas lie 

 between the trachese and in certain transverse 

 bands; their position corresponds to those of cer- 

 tain white markings of Ethiopian and Oriental 

 species. 



N. L. Partridge, University of Illinois: The 



Tracheation of the Pupal Wings of some Sa- 



turnians. 



A method of preparing permanent mounts of 

 lepidopterous pupal wings was described. The 

 pupal wings were removed in the customary man- 

 ner and the specimens secured, floated upon clean 

 water to straighten the wings and remove any dirt 

 which might adhere to them. Then they were 

 placed on a clean, untreated glass slide, smoothed 

 and allowed to dry, without further treatment. 

 The result was a transparent mount showing all 

 the traoheoles as well as the tracheae. Some of 

 these mounts were used as lantern slides, giving 

 clear images on the screen. 



It was shown that a greater amount of varia- 

 tion was found in the pupal wings than in the 

 adult wings. The homologies between the tracheae 

 and veins, of the specimens shown, was indicated. 



L. B. Walton, Kenyon College: Studies on the 

 Mouth-parts of Bhyparobia maderiw {Blattidce) 



