MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 



79 



side margins produced, dorsal surfaces with two, and on the prothorax with several, rows of short, hlunt spines. 

 Sides of prothorax less strongly rounded than the following segments ; each with a pair of moderately long legs, of 

 two joints and a terminal claw-joint representing the tarsus; tibia clothed with spiuules. Abdomen of nine stron«dv 

 transverse segments, each with a row of six blunt spines above, which are replaced by sharp spinules on the ventral 

 surface, terminal segments bearing a pair of moderately long appendages, with one short, cylindrical basal joint, the 

 remainder setiform, very obscurely multiarticulate. Anal prolongation stout, tubular, ending in four fleshy lobes, 

 which are usually retracted into the rectum. Stigmata, nine pairs; the first pair large, situated in the fold at the 

 hind angles of prothorax, the eight remaining pairs ou the first eight abdominal segments, at the middle of the edge 

 of the dorsal shield, and immediately below a short tubular spine (the last spine of the dorsal row). 



The larva of Adelops presents the general characters of Silphid larva? as given by Erichsoo, but is most closely 

 allied to those of Liodes and Agathidium. From the larger Silphidae it differs notably in possessing a movable labrum, 

 not soldered to the clypeus, and from all described larvae of the family in having the palpigerous pieces of the lower 

 lip (labium) widely separated, forming in fact a third joint of the palpi, and in the size and prominence of the ligula. 

 There are no long seusitive hairs upon any part. Of the larva of Catops, its nearest ally, no description is known to 

 me, except that of C.fuscus Gyll. by Erichson, which is too short to be of use. 



The pupa (Fig. 21 : a, ventral ; 6, dorsal view, enlarged ten times ; c, anal appendage, much enlarged), now first 

 made known, is characterized as follows : 



It is short, thick, almost conical, broadly rounded anteriorly, suddenly tapering behind, sparsely covered with 

 fine hairs. Head bent downwards upon the breast, not visible from above; upper lip prominent, emarginate; tips of 

 palpi projecting, free, constricted at the joints. Antennae bent up- 

 wards and backwards, lying back of the knees, in the concavity of 

 the prothorax, and projecting beyond the dorsal surface at its hind 

 angles, constricted at the joints, the outer half a heavy club, each 

 articulation of which bears large, spiny tubercles. Prothorax very 

 large, almost hemispherical, covering the body like a hood. Wings 

 folded over onto the ventral surface, lying under the anterior legs, 

 covering the thighs of the last pair. Dorsal surface almost entirely 

 exposed ; at the base of the wings three conical protuberances 

 placed close together, the largest ou the median line covering the 

 scutellum, the two smaller on either side upon the elytra ; the tip 

 of the metathorax protuberant, acutely prolonged over the first ab- 

 dominal segment. Abdomen strongly arched downwards, termin- 

 ating in two thigh-shaped appendages, with two or three long 

 hairs on the sides, aud a curved bristle at their apices ; between them, at the base, a lobe surmounted by two con- 

 verging tubular processes. Color, transparent white. Length, 2.5 mm — . 10 inch; width, 1.5 mm =. 06 inch. 



Fig. 21. — Adelops hirtus : a, pupa, under side ; 6, pupa, from 

 above; c, anal appendages (after Hubbard). 



VARIATIONS IN THE SPECIES OF CAVE COLEOPTERA. 



Anophthalmus tellkampfii. — la twenty-seven specimens from a single area, the Labyrinth, in 

 Mammoth Cave, there were very slight variations in size; all were about .30 inch in length, none 

 over; the smallest was .27 inch long. Mr. Hubbard found "but little variation "in forty speci- 

 mens. 



In twenty-five specimens from Diamoud Cave the only differences I could observe was in size- 

 the largest was .30 inch, the smallest .25 inch. 



Among sixty five individuals collected by Mr. Sanborn in "Long Cave, nearly one mile from 

 daylight, beetles at several damp localities, May 11;" the longest was .30 inch, the shortest was 

 .25 inch, both being males. There vere no other variations, except that the shortest has a very 

 slightly broader prothorax, though this is almost imperceptible. The color of all is the same, and 

 there is a remarkable uniformity in them, except a few pale ones recently out of the pupa state. 



In fourteen specimens from Sugar-Bowl Cave, 3 miles northwest of Glasgow Junction the 

 largest individual was .30 inch and the shortest .25 inch in length. They did not differ from 

 Mammoth Cave examples. Eleven specimens from White Cave did not differ from Mammoth 

 Cave examples; they were .30 inch long. Twenty-two specimens from Salt Cave showed abso- 

 lutely no difference from Mammoth Cave ones, and no perceptible variation from a length of .30 

 inch. 



Anophthalmus menetriesii from different caves varies somewhat in size. In ten specimens fj om 

 Diamond Cave the variation is only in size; the longest being .22 and the shortest .19 inch in 

 length. (" Of twelve A. menetriesii, three show considerable variation in size and form and one 

 is plainly pubescent." Hubbard.) 



