MEGASCOLECIDAE 285 



Copulatory papillae apparently absent. Dorsal pores absent. Gizzard small, cylindrical, 

 muscular, in segment 5. Salivary glands stop at septum 4/5. Intestine widens from the 

 oesophagus in segment 18, not in 17 as described by Beddard for a type specimen. This 

 character is probably variable, as in the three specimens of Microscolex michaelseni 

 hermitensis described above. Typhlosole absent. Lateral hearts, last pair in segment 11. 

 Nephridia with small pear-shaped terminal vesicles. Ovisacs present. 



Prostates occupying eight segments each, of which the duct is confined to the first 

 two. Duct straight and half as thick as the gland; gland moderately thin, tubular, 

 straight (not coiled as described by Beddard for a type specimen), sharply separated 

 from the duct. 



Penial setal sac muscles originate from the body-wall at, or at about (the state of 

 preservation leaves this character in some uncertainty) the i6th intersegment behind 

 their respective prostatic pores, i.e. at about intersegment 33/34. Penial setae: Beddard 

 originally described the penial setae as of two sorts, one fully twice as long as the other, 

 but otherwise alike and unornamented. Michaelsen later re-described the penial setae 

 but did not mention the question of dimorphism ; he described them as ornamented, but 

 was unable to observe this in some specimens (from Punta Arenas, South Patagonia). 

 In the present specimen the setae of the two sub-bundles are dissimilar; those of the a 

 bundle are three times as long as those of the b bundle and are apparently smooth, 

 while those of the b bundle are ornamented. Penial setae of the a bundle are strongly 

 curved when removed, but apparently lie straight in the setal sac; approximately the 

 distal half is somewhat flattened and broadened so as to appear strap-like when turned 

 about, the extreme distal end (Fig. 2 //) forming a thin, bluntly pointed, scoop-like 

 blade. Dimensions of a setae: length approximately 10 mm., diameter near base about 

 26/x, in proximal half of stem 1 4-1 5-5 /x, distal half 8-1 iju thick and 15-18)11 broad, near 

 the blade 12-5-14^1 broad, thickness of blade about 1-5/^1. Penial setae of the b bundle 

 with a straight stem curved only at the distal end, tapering gradually and terminating in 

 a flattened but not broadened blade which ends bluntly (Fig. 2 g), the distal half of the 

 stem ornamented with rows of fine close-set teeth. Dimensions of 6 seta: length 3-6 mm., 

 diameter near base 33-5/x, in middle of stem 20-21-5^^, near distal end 11 ^i, breadth of 

 blade 7-5^. It seems probable that Beddard was correct in describing a dimorphism of 

 penial setae for the types of this species, but that he failed to observe the ornamentation 

 of the outer setae ; Michaelsen on the other hand appears to have overlooked the lack of 

 ornamentation of the a setae, but it is possible that in his specimens the a setae were also 

 ornamented. 



Spermathecae : the spiral diverticulum is to the outer side of the ampulla and duct, 

 not to the inside as figured by Beddard ; it is also considerably thicker (Fig. 3 b). On the 

 left side the direction of the spiral is clockwise, on the right side anti-clockwise. 



In other characters, both external and internal, this specimen is in essential agreement 

 with previous descriptions. 



