SF.PTEXtnKR 7, 1SS3.] 



SCIENCE. 



387 



Up to tJiis time they have remained unhatched, and 

 will in all probability not hatch till next spring, thii* 

 ciirresponding to the ' winter egg' of the grai)e Phyl- 

 loxera. 



Psephenus Lecontei; the external anatomy of 

 the larva. 



BY D. S. KELLICOTT OF BCFFAI.O, N.Y. 



The sjieeies referred to is found in large numbers 

 at tlie rapids above the falls of Niagara, and is 

 scattered throughout the north-eastern part of Xortli 

 Americii. The author proposed to supplement the 

 accounts given of it by earlier observers witli a 

 record of liis own observations, which ilifterod in 

 some respects from those of Dr. LeConte. Sev- 

 eral details of anatomical structure were brought to 

 the attention of the members, and illustrated with 

 wood-cuts prepared for the purpose and with sjwci- 

 mens mounted in balsam for observation under the 

 microscope. 



The Psyllidae of the tTnited States. 



BY C. V. RII.F.Y OF W.\SinN(iTOX, I>.0. 



TiiK Psyllidae, or flea-lice, are rather small homop- 

 terous insects, that Iiave remarkable jumping powers. 

 Some of them injure cultivated plants. This is nota- 

 bly true of the Psylla pyri, which blights the buds of 

 pear-trees; and Pliylloplecta tripunctata. which crum- 

 ples the tips of the blackberry. The family has re- 

 ceived little attention in the United States, and 

 scarcely any thing has been known of the life-history 

 and develo|)ment of the species. The paper enumer- 

 ates 17 described species, four of these being syno- 

 nymes, and one of them (Psylla pyri) introduced 

 from Europe. They fall into four subfamilies, and 

 represent four genera already characterized, and three 

 new genera, — Urachylivia, Pachypsylla, and Phyllo- 

 plecta. The new species characterized are Calophya 

 vitreipennis, from Arizona; C. nigripennis, on Khus 

 copallina; C. llavida, on Rlius glabra; Pachypsylla 

 celtidis-cucurbita, forming galls on Ccllis texana; P. 

 c.-pubescens, P. c.-asteriscus, P. c.-umbilicus, and P. 

 c.-vesiculuni — all forming galls on leaves of Cellis 

 occidentalis ; Bl.astophysa (uov. gen. ) c.-gemma, form- 

 ing galls on the twigs of the same tree; Ceropsylla 

 (nov. gen.) xj'deroxyli, a remarkable form developing 

 in pits on the leaves of Xyderoxylon masticodeudron; 

 Trioza sanguinosa, on Pinus australis; T. sonchi, on 

 Sonchus arvensis; and Rhinopsylla Schwarzii, from 

 the cypress-swamps of Florida. The paper records 

 discoveries as to the entomography of the species, 

 and espeoi.illy tliose alTecting Rhus and Celtis; the 

 latter forming a group peculiar to North America, and 

 the most i)erfect gall-makers in the family. 



The most interesting portion of Professor Riley's 

 pa|)er, to those wlio are not entomologists, was that 

 where he dwelt on the life-histories and habits of the 

 insects he described. The eggs are attached to leaves 

 by a pedicel, and are somewhat pointed at one end, 

 and often terminate in a filament. The young are 

 broad and flattened, with a fringed margin. They 

 are generally jiale, ami more or less covered with a 



floeonlent secretion. Those on sumach are dark, and 

 without such floceulence. Those making galls on 

 h,iekl)erry have stout spines at the end of the bmly, 

 by the aid of which they are able to work out of their 

 galls. 



Note on Pbytoptidae. 



BY IIKIiUEKT OSBORy OF AMES, ID. 



The Pbytoptidae comprise a group of very minute 

 mites, species of which produce galls of various forms 

 on the leaves or twigs of various trees. Hecent in- 

 vestigation in Europe has placed the group in a dif- 

 ferent light from that in which it previously w.is 

 considered. Their study is rendered difficult by their 

 extreme minuteness, and the care necessary to dis- 

 cover the different stages. One of the most common 

 species produces the little wart-like swellings which 

 occur so abundantly on soft maple leaves. A species 

 on .-jsh leaves produces a swelling which is nearly 

 uniform on the upper and iimler surfaces of the leaf; 

 while another species on the same tree produces a 

 leafy growth at the end of the twigs, the growth 

 sometimes being inhabitcil also by cecidomyian 

 larvae. On the elm occurs a large deformed leafy 

 growth, which also contains Phytopti : while still 

 another form of gall occurs on box elder, consisting 

 of a depression on the under surface of the leaf, this 

 dipression being filled with a woolly growth, and 

 eontaining Phytopti. 



Notes on the potato-beetle and the Hessian 

 fly for 1883. 



BY E. W. CLAYI'OI.E OF NEW BLOOMFtELD, PENN. 



The author found that only one brood of the po- 

 tato-beetle appeared Last year. This seemed an un- 

 usual fact, but no second brood had a)>peared on 

 the potatoes under his observation. In the present 

 year, no beetles appeared during the early stage of 

 the growth of the plant. This fact Iiad been also 

 noticed in New York and New Jersey. lie attrib- 

 uted the cessation in the early ])art of this year to 

 the same unknown cause whicli had checked the late 

 brood of last year, and asked the opinions of members 

 in determining the cause. Professor Riley thought 

 the disappearance of the beetle couUl be attributed to 

 the drought. But Professor Claypole said that in 

 issi, which was an unusually liot and dry season, 

 the beetles were more numerous than he had ever 

 seen them, an<I gave him more trouble than ever 

 before or since. 



In regard to the Hessian fly. Professor Claypole 

 was of opinion that the in^ect injureil the later 

 wheat much more than the early crup. because the 

 crops that gain full strength are best able to resist 

 the attack. Wheat sown before Sept. 10 escaped the 

 ravages of the fly. The winter wheat U'ing chiefly 

 attacked, the observations on the insect had been 

 directed especially to that crop. Contrary to the 

 opinion of many farmers, Profes-or Claypole believes 

 there are two broods, one in the autumn, and one 

 ill the spring. The insect, it is thought, often 

 killed the stalk in the fall, ami then probably died 

 with it. 



