MOORE: HIRUDINEA OF SOUTHERN PATAGONIA. 683 



preserved for the purpose, many examples of this species exhibit a part of 

 the dorsal sensillae. In no case could the full number be detected on any 

 one somite and it is possible that the dorso-median series may be wanting. 

 At any rate the pair most median in position are separated by a wide 

 interval, equal to about half the width of the body. Plate L, fig. 24, shows 

 their arrangement on somite XXIV of an individual in which they were 

 especially prominent. 



Pigmentation. The color above is a pale brownish, with a broad 

 median dark area (equal to two thirds of the width of the body) marked 

 by twenty-four fine longitudinal lines of black pigment cells, which corre- 

 spond to as many intermuscular intervals. The two most mesial of these 

 are much heavier than the others and tend to unite across the median line. 

 All of these lines, and consequently the area, tend to fade out both ante- 

 riorly and posteriorly. More superficial than the longitudinal striae are 

 small irregular blotches and transverse dashes which lie between the cir- 

 cular muscles and are more or less thickly scattered over the entire dorsal 

 surface from margin to margin, except anteriorly, where they are very few, 

 and further forward altogether absent. These spots give to the dorsum 

 a speckled appearance not unlike what is seen in many examples of G. 

 scittifera. Of course some individuals are lighter, some darker. Many 

 examples have two or three large irregular whitish spots, from which pig- 

 ment is nearly or quite absent, in the posterior part of the body. A some- 

 what unusual feature in members of the genus is the presence on the 

 ventral surface of submarginal series of irregular, more or less confluent 

 dark spots, forming a band on each side. They are confined to the middle 

 third of the body. 



Reproductive Organs. The genital pores are separated by a single 

 annulus, the male being at XII aila2, the female XII a2/aj. There are 

 six pairs of testes arranged as in G. duplicata. The vas deferens is dorso- 

 laterad of the testes and is met by the six delicate vasa efferentia, which 

 arise from the dorso-lateral aspect of the testicular walls. After reaching 

 somite XII the vas bends back into a long epididymal loop as in G. dupli- 

 cata, but, instead of becoming enlarged at once to form the sperm sacs, 

 as in that species, it reaches, without any change in its diameter or the 

 character of its wall, as far caudad as XVI or XVII, at which point it 

 abruptly passes into the sperm sac. The latter may extend as far as 

 XX, and the anterior end of its efferent limb becomes more or less coiled 



