994 The American Naturalist. [Mareh, 
Thus in our Pear-tree Psylla we have a case of true dimorphism. The 
summer form is the typical Psylla pyricola, and may be designated 
when necessary to refer to this form alone as Psylla pyricola pyricola; 
while the hibernating form should be known as Psylla pyricola simu- 
lans.” 
Experiments showed that the immature stages of the Psylla were 
easily destroyed by spraying with kerosene emulsion. Weare indebted 
to Mr. Slingerland for the use of the engravings on the accompanying 
plate, showing the stages and structure of the insect. Fig. 1 repre- 
sents the adult insect; fig. 2, its head and antenna greatly magnified ; 
3, the abdomen of the male; 4, the abdomen of the female ; 5, the 
wings; 6, the full-grown nymph, and 7, the egg. 
Insects of Southern Alaska.—An important contribution to our 
knowledge of the coleopterous fauna of Southern Alaska has recently 
been made by Mr. H. F. Wickham,’ who has published some of the 
results of a collecting trip made during the summer of 1891. The 
points visited were Fort Wrangel, mainland near Wrangel Island, 
Yes Bay, Loring; Hunter’s Bay and Port Chester in Alaska, and the 
Stikine River Valley and Glenora in British Columbia. From his 
studies Mr. Wickham concludes (1) “That the fauna of Southern 
Alaska is less closely related to our alpine, northern inland or north- 
east coast faune than is that of the Stikine Canyon or of Glenora. 
(2) That the Stikine Canyon fauna is more closely allied to that of 
the north and east than is that of the coast, and about the same as is 
that of Glenora. (3) That the chief relations of all three are in the 
direction of Lake Superior. With larger lists this affinity might turn 
to the Rocky Mountains, especially in the case of Glenora.” 
Notes on Ohio and Other Phalangiidz.— A recent study of a 
large collection of harvest-spiders (Phulangiide) from all parts of 
Ohio shows that the State is unusually rich in these interesting Arach- 
nids. The following species occurred in the collection : 
1. Liobunum vittatum (Say) Weed. 
2. Liobunum vittatum dorsatum (Say) Weed. 
3. Liobunum nigripalpis (Wood) Weed. 
4. Iiobunum nigripes Weed. 
5. Liobunum politum Weed. 
6. Liobunum longipes Weed. 
2Entomology of Southern Alaska, Bull. Nat. Hist. Labrt. Iowa State Univ., V. ii, 
pp- 202-233. 
