THE AMERICAl^ ENTOMOLOGIST. 



113 



t^ 



BIiAI>DER-PLUxUS, 



For many years we have noticed in tlic iiiid- 

 ille of June on particular trees of our common 

 wild plum {Prunus (imeriv<nm) , tliat many spe- 

 ciuiens of the fruit were enlarged to thrice their 

 usual size and were uneven and wrinkled on their 

 external surface instead of being' smooth and 

 plumply rounded. On cutting into such speci- 

 mens, they are found (o be hollow and spongy 

 inside, instead of solid and Hcshy; and almost 

 entirely detached from the exterior rind, there 

 lies in the centre the juicy white stone which is 

 found imbedded in the llcsh of the normal plum 

 at this season of the year. On the closest ex- 

 amination, we could never detect in these dis- 

 eased plums any tokens of the operations of 

 insects. 



Ou June i»th, 1868, A. Gilbert, of Tipton, 

 Iowa, sent us two pressed specimens, similar 

 to those which we had ourselves found on the 

 Wild Plum, but gathered from his own plum- 

 orchard. He did not specify what varieties of 

 jilum he had in cnltivatiou, but lie stated that 

 with him the disease commenced about four 

 years ago, and has now taken almost complete 

 possession of his trees. Hence it would appear 

 that, besides the Curculio, there is still another 

 destructive pest which the unfortunate plum- 

 grower has to guard against. Verily, this work 

 of growing plums seems to be "the pursuit of 

 fruit under difliculties."' 



>Vc can guarantee that this bladder-like de- 

 generation of the plum is not caused by any 

 insect. What, then, does cause it, if insects do 

 not? "We answer that, in all probabilit;, it is 

 caused by a peculiar parasitic fungus, which 

 may, or may not, be identical with one which 

 produces very similar effects in Europe. In the 

 London Periodical called Science Gossip, for 

 August 1st, 1801), we notice an observation that 

 liladder-plums, which are described as being 

 almost exactly like our American ones, are 

 common on the Sloe or Blackthorn (Prtntus 

 spinosa) in England, and that they are said to 

 i>c caused by a Parasitic Fungus (Ascomyces 

 ilefurmans). The fruit presents none of its or- 

 dinary succulent characters, the stone is not 

 formed, and the ovule is more or less atrophied, 

 while sometimes a second carpel is produced. 

 From a recent article on Peach l!ot byDr. T. C. 

 Ililgard of St. Louis, we learn that that gentle- 

 man had had such specimens scut him from 

 Europe by the distinguished botanist, Dr. G. 

 Engehnann of St. Louis; and that from their 

 showing "'an empty, degenerated and inllated 

 germ," they were popularly knowu there as 



"fools."' The tree ou which they occurred is 

 said by Dr. Ililgard to be " Prunits j'ctdiis," 

 which Gray describes as a small Bird Cherry, 

 which is occasionally planted in this country, 

 and resembles the Choke Cherry, but has longer 

 and looser, and often drooping racemes, and a 

 roughened stone. 



"We have on one or two occasions received 

 these " Bladder-plums " from correspondents 

 in Missouri, and Dr. L. D. Morse, and Juo. H. 

 Tice of St. Louis, bolh have found them on the 

 wild Chickasaw plum; but Dr. Hull of S. Illi- 

 nois, informed us some time ago that he had 

 never met with them, and that he was entirely 

 unacquainted with any tuch disease. Hence 

 we infer that however destructive it may have 

 been elsewhere, it has not yet made its appear- 

 ance in Southern Illinois, and possibly may 

 never do so. 



THE TRUMPET GRAPE-GALh. 



{r;fi« vitn-ohi, o. s.) 



[Kig, 76.] 



Color— Cri: 



On page 28 of the present volume of the 

 AjiiiuicAN Entomologist we presented the 

 above illustration (Pig. 76) of this crimson 

 Trumpet Grape-gall, and in answer to D. Mc- 

 Clainc of Piermont, N. Y., stated that it was 

 produced by a gall-gnat, and that it was dcs- 

 scribed in our manuscriptB under the name of 

 Mtis litiius. We have since been inlornicd by 

 Baron Osteu Sacken that this gidl is liis Vitis 

 i-(7(Vo/a, very briefly described in (he "Mono- 

 graphs of the Diptcra of N. America." p. 202, 

 as an " elongated, conical, red gall, 0.25 to 0.;i 

 long; on the upper side of the leaves of the 

 grape." The gall will therefore be knowu by 

 the last name, our /iluus being invalid. Refer- 

 ring to this gull in a recent letter, Franciij 



