470 ENTOMOLOGICAL NEWS. [Dec, 'll 



mediate host has yet been discovered for H. nana. "Rats certainly 

 ingested a large number of fleas from time to time, but it was diffi- 

 cult to imagine that they would acquire a very large infection with 

 H. murina by this means; and if H. nana be identical with H. murina 

 it was scarcely conceivable that a human being could accidentally 

 swallow a sufficient number of fleas to give rise to an infection of 

 over a thousand tape-worms, as was frequently found to be the case. 

 It would still, therefore, be necessary to admit that the develop- 

 ment of H. murina usually took place without an intermediate host, 

 but that occasionally the rat-flea might function as such. With such 

 a conclusion the life-story of H. murina became even more re- 

 markable than before." (Proc. Zool. Soc, London, 191 1, part I, pp. 

 9-13, with figures of the two Cysticercoids.) 



Means of transporting fungi by the Ambrosia-beetles. — In the 

 current volume, No. 7, of Entomologische Blatter (which describes it- 

 self as an International Monthly for the Biology of European Beetles 

 with special reference to Forest Entomology), Strohmeyer describes 

 and figures in halftone some of the very curious bunches of bristles 

 to be found on the heads of the females only of various species of 

 Platypodidae. As in certain species {Mitosoma sp.) he found clumps 

 of Ambrosia fungus always adhering to the bristles, he infers that 

 the latter serve to transport the fungus from one place to another. In 

 conclusion he remarks that in a very large number of Platypodidae, 

 perhaps in more than half of all the species, a special apparatus for 

 the transport of fungus is lacking. Why are not all Platypodid 

 females so provided? To answer this question it is necessary to glance 

 at the habits and character of the food of these beetles. According 

 to the mutually confirmatory researches of Hubbard* and Negerf the 

 fungi of different Ambrosia beetles are diff'erent, the species of fungus 

 depending not on the kind of tree in which the beetle lives, but on the 

 species of beetle. It therefore results that the introduction of the 

 fungus into new brood-tunnels must be brought about — unconsciously 

 of course — by the beetle itself. Dr. Neger has shown that the fungi 

 which are associated with the German species of Xyleborus and 

 Xyloterics discharge their spores not as dust but in slimy balls, which 

 easily adhere to the unevenesses of the elytra and to the hairs. A fun- 

 gus with such peculiarities requires no special apparatus for its transport 

 on the part of its symbiotic beetle. Only when the fungus is wholly 

 or in part unable to be attached to the beetle does the need of some 

 special modification of the insect arise. 



* The Ambrosia beetles of the United States. Bull. No. 7, U. S. 

 Dept. Agric, 1897. 



t Aus der Natur IV, p. 921, 1908. Zeitschr. f. Land- u. Forstwirtsch., 

 1908, p. 274. Zentr. Bact. Par. Abt. II, Bd. XX, p. 279. 



