LEPTOECIA ABYSSORUM. 323 



apex, the guards narrowing abruptly at level of tip of seta, which it enfolds 

 proximally; the medulla is densely fibrillate, the fibrillae being somewhat 

 obUque and usually very dense excepting in the distal region. (Plate 37, fig. 8). 

 No crochets of this type are found in the type on the second parapodia, but in 

 their place occur stout setae gradually attenuated distad to a fine flexible tip 

 and narrowly limbate along one side, these on other parapodia caudad occurring 

 among the shorter of the usual bilimbate setae. 



The maxillae are thin and translucent, with the edges and the tips of the 

 first pair dark. Maxillae I have the carriers usually united along the middle 

 line to form a plate longer than wide ; the plate on each side toward the anterior 

 end is weakly incurved and commonly moderately bulging, caudad; the plate 

 is uniform in the tyj^e, the elevated triangular area being set off anteriorly only 

 vaguely; the blades are of the usual falcate form, the terminal portion slender 

 and well curved. Maxilla II of the right side has twelve teeth which gradually 

 increase in size distad, the most distal being conspicuously large and well sepa- 

 rated; the inner plate on the left side has thirteen teeth also increasing in size 

 distad, and the outer plate has eighteen teeth, of which the most distal one is 

 abruptly decidedly longer and stouter. Maxilla III of the left side has eleven 

 teeth, that of the right side has ten teeth. (Plate 36, fig. 3). The mandibles 

 are of good size but are thin and translucent. The masticatory plates are narrow 

 mesally and subclavately enlarged ectad; they are white and hard; below the 

 ectal end of each is a conspicuous notch separating it from the expanded sup- 

 porting part of the stem. The anterior edge of each plate is nearly smooth, 

 but slightly uneven, the two meeting at an angle of less than 90°. The stems 

 are long and, excepting at the ends, are parallel and of uniform width; they are 

 weakly united anteriorly and are pale throughout, excepting for a short but 

 conspicuous narrow black stripe on each along its mesal edge at the anterior 

 end. (Plate 36, fig. 4). 



The tube is straight, flexible, and transparent. It presents on each side a 

 slender, rather stiff, cylindrical, supporting rod. The membrane between the 

 two rods is thin and transparent. The tube is flattened at right angles to the 

 plane embracing the axes of the two supporting rods, its cross-section being some- 

 what lenticular. The transverse diameter is 3.2 mm. 



Locality. Between the Galapagos and Peru: Sta. 4647 (lat. 4° 33' S., 

 long. 87° 07' 30" W.). Depth 2,005 fms. Bottom of light grey and brown 

 Globigerina ooze. Bottom temp. 35.4° F. 9 November, 1904. One specimen. 



