Article beginning on page 278.
Psyche 2:278, 1877.

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On the Spiracles of Coleoptera and on the Sound Pro- duced by Polyphylla.
On 10 July 1874 I observed a male PolyphyUu variolosa (Hentz) making a creaking noise while moving its abdomen up and down under the elytra. Examination of the specimen shows upon the outer face of the spiracle-bearing plate of the metathorax an oblong, slightly swollen area, free from pubes- cence, of a thin texture and pale color. This is covered by the
elytra when the insect is at rest. At a corresponding point under the margin of the elytra is seen an area of similar size and of a pink color. The same structure is to be seen in the female Polyphylla, but what relation, if any, this has to the production of the sound it is difficult to understand. The existence of mesothoracic and metathoracic spiracles in coleoptera has recently (her. fit., 1874, p. 532) been ques- tioned, because of the absence of such spiracles in the larva. None are apparent upon the mesotl~orax of Polyohylla, but a more careful examination will discover that they are present here, since Strauss-Durckheim found them in Melolontha and Reinhard asserts their existence in the hymenoptera, notwith- standing that they are not externally visible. The metathoracic spiracles, however, are very obvious in Polyphylla, being placed at the inner margin of the membrane which forms part of the dorsal face of that plate which on its vertical face presents the structure noticed above. Behind these spiracles are situated seven additional pairs, a pair upon each segment of the abdo- men excepting the last. The spiracles of the prothorax and of the basal segment of the abdomen are larger than the others, although, being concealed in the sutures, they are to be found only by dissection. In Tenebrio, and many other coleoptera, , it is true, no metathoracic spiracles are apparent.. Dr. Packard states (1, c.) that in the coleoptera there are usually eight pairs of abdominal spiracles. This is manifestly incorrect in regard to the imago, for in no adult hexapod insect can more than seven pairs of abdominal spiracles be demon- strated. In larvae eight pairs is the maximum, but functionally the eighth pair belongs to the seventh segment and the first



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pair to the metathorax, and in changing to the imago each pair of spiracles is transferred to that segment to which it function- ally belonged in the larva. The typical number of spiracles in insects is ten pairs, and none are ever present in excess of this number, or which are not homologous with some of these. In Mr. Gissler's article in PSYCHE, vol. 2, p. 240, it is stated that the adult '~Amblychila has seven pairs of stigmata." De- siring to find what had become of the missing spiracles of the larva, I examined some specimens collected in Kansas and kindly presented by Mr. S. W. Williston, of New Haven. Without attempting to find the minute mesothoracic pair, which are not present in the larva, the prothoracic pair and seven ab- dominal pairs were easily discovered, making eight in all. The metathorax of Amblychila is very much 'educed dorsally, the wings are absent, and no spiracles are apparent on ti& seg- ment. The pair under the posterior edge of the prothorax are, as usual, very large. The spiracles of the abdomen dimin- ish in size to the last, which are nevertheless well developed. W. H. Patton.
BIBLIOGRAPHICAL RECORD.
(Continued from page 256.)
The date of publication, here given in brackets [ 1, marks the time at which the
work was received by the Editor, unless an earlier date of publication is known to him. An asterisk * before a title is the Recorder's certificate of accuracy of quotation. Cor- rections of errors and notices of omissions are solicited. - B: PICKMAN MANN. Nos. 1215 to 1266 are from Can. entom., 1877, v. 9. * 1252. Westcott, Oliver S. Food plants of H. maia. (Can. entom., 1877, v. 9, 13. 220.)
[See Rec., no. ll9l.I Hemileuca maia abundant in swampy localities. Does it not feed on other plants besides Quercus, Salk and Spiraea? [Dec., 18 77.1
* 1253. Peck, G: Williams. [Captures of rare lepi- doptera.] (Can. entom., 1877, v. 9, p. 220.) 3 species of Catocala and larvae of 4 species of Sphingidae captured in Roselle, N. J. [Dec., 1877.1
* 1254. Grote, A: Radcliffe. [A "seeming growth.'"] (Can. entom., 1877, v. 9, p. 220.)
[See Rec., no. 1 241. ]
Suggests that the " growth " referred to is a pol- len-mass. [Dec., 1877.1




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