8o 



THE AMERICAN ENTOMOLOGIST. 



a large nucleus or vacuole, occupying the lowe»W| 

 portion. They were not examined with high 

 magnifying powers, but may perhaps be stalked, 

 ciliate infusoria. Two of these bodies are repre- 

 sented attached to the antenna at Fic. lo, b. 



Adelops hirtiis Tellk. — (Fig. ig, a head of larva 

 from above, /', right antenna from above, c, labium, 

 left maxilla, etc., from below, all much enlarged). 

 The immature forms oi Adelops have never been 

 properly noticed. Packard's figure of the larva 

 (/. c. vol. X, pi, ii.) represents a much contracted 

 specimen, the body tapers too rapidly, and the 

 thoracic segments are nearly one-third too, wide, 

 antenna (Fig. 4, a, of his plate) is incorrectl}' drawn. 



The following description made from numerous 

 well preserved specimens, is an attempt to give 

 this larva the careful attention its importance 

 deserves : 



The body is stout and cylindrical, gradual!)' 

 tapering from the thorax, slightly compressed 

 above, dorsal shields covering the segments, very 

 thin and transparent. Color dull white, with the 

 head darker, and tips of mandibles alone tes- 

 taceous. Length 4.4"""=. 17 in. Head free, 

 nearly as wide as prothorax, rounded, convex, 

 [Fig, 19.] 



made appears to have been much mutilated, and his 

 figure (/. c. V, 751) is very incorrect. The head is 

 represented much too large, and the antennx are 

 reversed in relative position. Prof. _Cope de- 

 scribes, from the region of the Wyandotte Cave 

 a Cacidoten distinguished from C. slygia by its 

 smaller and more acuminate head (/. c. vi, 411 

 and 419). Apparently the comparison was made 

 only with Packard's figure, if so his species (C 

 microcephala) is very doubtfully distinct. The 

 external egg-pouches with which its body is made 

 to terminate, are certainly fanciful creations hav- 

 ing no existence in this Isopod crustacean. It 

 is difficult to understand how their number and 

 position could be determined in specimens which 

 " are in bad condition, having lost their limbs, 

 egg-pouches, and the distal portions of their an- 

 tennae." Packard's specimens had also lost the 

 longer antenna;, and neither of these authors 

 mention the existence of caudal stylets. 



The following additions and corrections will 

 aid in the determination of the Mammoth Cave 

 species : 



Inner, short antennae with from nine to twelve 

 joints, the first three subequal, much longer and 

 stouter than the rest, together making nearly half 

 the entire length of the organ ; fourth joint very 

 short, oblique ; fifth joint longer ; tlie remainder 

 diminishing in length and thickness to the end. 

 The four outer joints bear on the inside a flat- 

 tened, cultriform spine, terminal joint minute, 

 tipped with a bristle, bearing the cultriform spine 

 upon a projection at the side. Outer antenna; 

 nearly equal to the body in length, with three 

 large basal joints, the first short and stout ; the 

 second long, together with the first about equal 

 to the inner antennze ; the third equal to the two 

 first, and also to the thirteen following ; the re- 

 maining joints closely applied, transverse at first, 

 gradually diminishing towards the tip of antenna;. 

 In six specimens the number of short joints of 

 the outer antenna; was found to be, by careful 

 count, respectively 60, 57, 50, 40, 40 and 36. The 

 number of short joints varies also in the inner 

 antenna;, and is not always the same in both 

 members of the same pair. The caudal stvlets 

 are long; flattened, two-branched ; the longer 

 branch terminal, bent downwards : the shorter, 

 spindle-shaped, directed outwards from near the 

 apex ; both are tipped with a few bristles. The 

 stylets vary from 3,5""" to 2,75""" in length. 

 Measurements of a large number of specimens 

 show great variation in size, the length of the body 

 proper ranging from 4 to 9""" and the appendages 

 varying in specimens of tile same size. The 

 specimen here figured is of mediuiii size, and 

 gives the following measurements, — length of 

 body 7'""' = . 28 in., long antenna; 6. 25""" = . 25 in., 

 stylets 3. 5"'"' = . 14 in. 



Clustering about the head and base of antenna; 

 in some specimens are seen numbers of minute 

 pear-shaped organisms, covered with hairs, and 

 attached to the surface of the crustacean by thread- 

 like pedicels ; a short tube, or cylindrical pro- 

 jection is sometimes visible near the apex, and 

 the contents appear to be granular with usually 



Adelops hirtus : «, head of iai-v.-i from above j /', antenna ; 

 r, underside of head (after Hubl>ard). 



broader than long, sides slightl)' rounded, trun- 

 cate in front, sparsely covered with fine hairs. 

 No ocelli. Antenn;e arising from the convex 

 sides of the head, just before the middle, directed 

 backwards ; of four joints, the first tuberculous, 

 the second elongate-cylindrical, slightl}' enlarged 

 anteriorly, the third twice as long as the second, 

 slightly curved, thickened on the inner (anterior) 

 side, sparsely covered with bristles, a longer 

 bristle on the inside at the thickest portion, a 

 stout spine on the inside at apex, fourth joint 

 appendiculate, bearing lateral bristles and a shoit 

 spine at tip. Epistoma prominent trapezoidal, 

 strongly angulate, edges straight. Labrum mov- 

 able, dcflexed, transverse, oval, bearing spines 

 above and below. Mandibles stout, lobed at 

 base, with molar surface striate, moderately 

 curved, bidcntatc at tips, overlapping when 

 closed. Maxilla; large, prominent, passing the 

 mandibles, protuberant and strongly angulate at 

 base, consisting of elongate cardinal and basal 

 pieces, and a pyramidal palpigcr, obscurely sep- 

 arated into two lobes by a longitudinal furrow, 

 the upper lobe bearing internally four or five 

 spines, the lower lobe terminating in a curcvd, 

 ciliated crest; maxillary palpus, arising from the 

 base of the palpigcr, of two stout basal and one 



