354 The American Naturalist. [April, 
border of Ohio to Lake Erie. I may cite, as example, Dromogomphus 
spoliatus, which, until taken by me at Toledo, was recorded only from 
the extreme south. I do not remember to have seen it in any private 
or public collections. This year, along the Maumee River, it was ex- 
ceedingly abundant.” 
Changes of Intestinal Epithelium in Tenebrio.—Herr C. 
Rengel has studied the changes of the intestinal epithelium in the 
metamorphosis of the Mealworm (Tenebrio molitor) and compared 
them with those occurring elsewhere. Regenerative cells, from which 
the new epithelium is derived, appear as subepithelial islands in very 
young larve, but it is only when the metamorphosis begins that they 
give rise to the elements which form the invaginal epithelium. As in 
Muscidæ the disruptions begin with an energetic contraction of the 
muscular layer, and the old mid-gut epithelium is raised off. Its dis- 
integrating cells are held together in a “cyst” by their membranea 
propria, and form the “ yellow body.” The muscles undergo gradual 
disruption without active invasion by phagocytes as occurs in Muscide. 
Korotneff compared the two modes to chronic and acute pathological 
processes. As soon as the larval muscular layer had been disrupted, 
nuclei are seen surrounding the epithelial cylinder. Whether these 
nuclei are old or new elements is doubtful, but the small cells of which 
they form the centers become the fibrils. Rengel’s opinion is that 
many muscle-cells survive the general revolution, just as a large num- 
ber of epithelial regeneration cells persist. The latter give origin to 
the epithelial cylinder, the former to the mnscular layer. (Journ. 
Royal Micros. Soc.) 
PSYCHOLOGY.’ 
Dreams.—At the Psychological Congress last year, Dr. J. Mourly 
Vold, of Christiania, reported some experiments which he had under- 
taken with regard{to the artificial stimulation of visual elements in 
dreams. The subjects included a large number of persons of different 
ages, sexes and classes, but were mostly adults of an intellectual type 
above the average ; all those selected were good dreamers. Dr. Vold 
arranged the experiments as follows: To each of his subjects he sent, 
from time to time, a package containing figures of animals, well-known 
objects, ete., cut out of white paper, or some striking colored object— 
1 Edited by H. C. Warren, Princeton University, Princeton, N. J. 
