552 PROCEEDINGS OF THE ACADEMY OF [Juty; 



to an acute point. Like the compound seise they are superficially 

 granulated and they are much elongated in the genital region. 



A majority of the specimens have the proboscis protruded to various 

 degrees, one to a length of 16 mm., but in no case as far as the jaws. 

 It increases slightly in diameter from the base distally, where it may 

 equal 1.5 mm. in diameter. In the best preserved examples it is fluted 

 longitudinally by about 18 parallel muscular ridges. The entire sur- 

 face is covered thickly with stiff cuticular papillte arranged rather 

 regularly in longitudinal rows, to correspond with the ridges. These 

 papillffi are of various sizes, varying from .065 mm. to .02 mm. in height, 

 but chiefly divided into a large and a small set, of which the former 

 crown the ridges and the latter occupy the furrows. These papillae (fig. 

 48) are colorless and stiffened by a thick striated cuticle, have broad 

 trilobate bases with the paired lobe forward and the elevated portion a 

 broad-based, pointed and slightly hooked cone, the cuticular covering 

 of which has a deep cleft running up the anterior face and terminating 

 in a pore near the apex. 



In the retracted state of the proboscis the position of the jaws varies 

 from somite XXXVH to XLII. The jaws are black and ^'ery hard, the 

 principal pair nearer together ventrally than dorsallj-. The latter 

 (fig. 47a) bear 3 or 4 large claw-like fangs which diminish in size medi- 

 ally and point caudal. The accessory jaws are of much smaller and 

 variable size, the dorsal arch containing 14 to 16 besides a few very 

 minute ones. They (fig. 476) have bases Avhich are deeply bilobate 

 anteriorly and broadly unilobate behind, and usually bear a pair of 

 equal divergent claws but sometimes 3 or 1. The ventral jaws are 

 similar and 7 or 8 in number and with the others form an unbroken ring. 

 Anterior to this ring is the jaw sheath consisting of a circle of about 18 

 soft papillce. The chevron-shaped jaws form lateral longitudinal 

 series of about 20 at the base of the extended proboscis. As the largest 

 ones occur in the middle of each series and smaller ones at the ends, 

 they form elongated elliptical areas tailing out behind where several 

 quite rudimentary denticles occur. 



Considerable individual variation is exhibited in the colors, which 

 have resisted the solvent action of the alcohol c[uite well. Generally 

 the ground is a yellowish-brown, showing a strong tendency to an annu- 

 lar arrangement in the anterior region where the furrows are pale. 

 Posteriorly it is generally darker and more imiform. Most specimens 

 are more or less blotched or even strongly annulated anteriorly with 

 dark purplish-brown, and each segment in the genital region is marked 

 by a, sometimes very conspicuous, pigment spot at the posterior mar- 

 gin in the median ventral line. 



