June iSSS.] 



PSYCHE. 



71 



ENTOMOLOGICAL ITEMS. 



Omission. — Owing to the length of our 

 leading articles the Bibliographical record 

 will be omitted from this numero of Psyche. 



Mr. C : H : T. Townsend has gone from 

 the War department, Adjutant general's of- 

 fice, to the U. S. Department of agriculture, 

 Washington, D. C, which is his present ad- 

 dress. 



Platypsylla surely coleopterous. — 

 Drs. G : H : Horn and C : V. Riley, working 

 independently, have studied the larva of 

 Platypsvlla castoris, and state that the larval 

 characters fully prove that the insect is 

 coleopterous. 



Dr. G : H : Horn visits Europe again this 

 season. The Doctor needs this recreation 

 and we know he will bring back with him 

 fresh energy that will enable him to continue 

 his valuable work. His address will be : Care 

 of Dr. D. Sharp, Shirley Warren, Southamp- 

 ton, England. The Doctor will leave May 9th 

 and will be gone all summer. — Entom. ainer- 

 icana, Maj' 1SS8, v. 4, p. 36. 



A CURIOUS MiTK. — A species ot hydrach- 

 nidae, found by Dr. Otto Zacharias in a 

 little mountain stream, the Iser, in northern 

 Germany, and known, on account of its 

 large dermal glands, as sperc/iou sflauduiosus, 

 has been found lately in the fresh waters of 

 the Azores, by Prof. Barrois, of Lille, France- 

 Dr. Zacharias calls attention, in the Monate 

 liche mittheilungen aus dem gesammtgebiet- 

 der ttaturtvissetisckaften (Dec. 1887, jahrg. 5, 

 p. 215), to the curious fact that in both these 

 distant localities this species is found only in 

 such ponds and streams as have a temperature 

 of 15-15.5° C. 



Ant-inhabited plants. — Hernandez, 

 about the middle of the seventeenth century, 

 described the stipular thorns of Acacia cor- 

 nigera of Central America, into which certain 

 .ants eat, feed upon the pulpy interior, and 

 live in the dwelling thus made. Such in- 

 habited thorns g'-ow larger and distorted, 



and the ants seem to pay for their hospitality 

 by protecting the tree from other marauding 

 insects. Two woody Rubiaceae of Sumatra 

 were described in 1750 by Rumphius, as in- 

 habited by ants. They are both epiphytic 

 and attached to the host tree hy a large tuber- 

 ous base, which is cavernous and occupied by 

 ants. The ants, by their irritating presence, 

 cause the tuberous growth to enlarge, but 

 the enlargement begins during germination 

 before the ants attack it — an instance of a 

 plant preparing beforehand for expected 

 guests. It is said that seedling plants which 

 fail to become inhabited, perish. Dr. Gray, 

 in a review, says that "it is most supposable 

 that this extraordinary formation was ac- 

 quired gradually; that the normally fleshy 

 caulicle of the ancestral plant, made a nidus 

 for an insect, developed under the disturbing 

 stimulus somewhat as a gall develops, until 

 at length, the tendency became hereditary, 

 and the singular adaption of plant to insect 

 was established.'" — Botan. gazette. 



Photographs of Cobwebs. Mr. Horace 

 P. Chandler of Boston has made a very suc- 

 cessful photograph of an Epeira web by tak- 

 ing it early in the morning while it was 

 covered with dew. A copy of this photo- 

 graph is in the collection of the Boston 

 Society of Natural History. The web hangs 

 between the branches of a spruce tree and 

 looks like that of Epeira triaranea though 

 unfortunately the spider was not preserved 

 for identification. 



Amateur photographers can render good 

 service by further experiments in this direc- 

 tion, taking care, each time, to preserve the 

 spider in alcohol with a complete record of 

 time, place and surrounding. 



The following webs are good subjects for 

 photography and often hang in convenient 

 places : all the flat, round webs made by 

 Epeira and its allies the web of Linyphia 

 margi7tata, which consists of a flat dome 

 three or four inches in diameter, held up by 

 an irregular mass of web, extending upward 



