K) BULLETIN OF THE BROOKLYN KNT. SOC. 



non-chitinized and retractile ; its position is in a minute cavity 

 which is surrounded by a semi-circular ridge.* 



What I formerly called "penicilli" may be better termed "artic- 

 ulated spines", (fig-. 4.) The integumental appendages of larva! 

 pygidia may be regarded a 6 * homologa of the dorsal parapoda of 

 their ancestors, the Annelides. 



In exuviations these organs are also cast off together with the 

 bristles etc., of the entire integument. Their position and struct- 

 ure allow them to yield to slight pressure, but they are not coor- 

 dinate by will since no muscular fibres could be found to move 

 them. The terminal nerve-branches, arising from the 8th (last) 

 abdominal ganglion, I was able to follow — in young individuals 

 —not farther than to the two propellers. 



Two very minute tubercles can be seen under higher microscopic 

 power at the middle of base of pygidial tips in Eleodes. Whether 

 they are orifices or not I cannot decide. The larger individuals 

 of Eleodes-larvae, when disturbed and handled, violently jerk their 

 abdomen and spurt a turpid, odorless and watery liquid out of 

 two lateral orifices situated under the tergal fold near the posteri- 

 or margin of the 7th abdominal segment. 



This organization is a peculiar adaptation to the larval body 

 since the excretion of the repugnatorial gland in the imago is 

 spurted out through the anal opening. The higher developement 

 of this gland is certainly attained during the chrysalis-period. 



The gibbosity of the 2nd (chitinized) antennal joint of Blaps, 

 Tenebrio and Eleodes is in every case on the outer side of the joint. 



But little attention has been paid to slight differences in the 

 forms of maxillae and maxillary palpi and for sake of comparison 

 but two have been figured (fig. 2 and 15). The maxillary spines 

 are in every case not articulated but deeply inserted into the 

 mando of maxilla. The tips of maxillary palpi of Boletotherus is 

 covered with what may be termed "sensitive aciculi" (fig. 16). 

 The same are also on tips of labial palpi. A median canal runs 

 through the tip of the maxillary palpus (which is lacking in labia] 

 palpus), and, though I could see no aperture, appears to indicate 

 the seat of a sensitive bristle of the 1st post-embrionic stage. 



* It is somewhat doubtful whether this soft, integumental process deserves 

 to be called "joint," though Wm. Ji. Erichson describes the t>ame as the first 

 joint hi the larva of Tenebrio. See Arehiv fuer Naturgesehichte. 1841 p. 

 365. 



