LEPIDASTHENIA CURTA. 63 



dorsal cirrus is attached caudad of the middle of the parapodium and extends 

 distad to or a little beyond the tips of the neuropodial setae; it is terete and 

 acuminate to a fine tip like the tentacles and tentacular cirri; the cirrophore is 

 a thick and conspicuous eminence. The ventral cirrus is attached distad of the 

 middle; it is a short, slender, subulate process not reaching to the end of the 

 neuropodiimi. 



No notopodial setae detectable on any parapodia of the type. The neuro- 

 podials are arranged in subvertical series which may embrace eighteen to twenty- 

 fom- setae spreading out from each other distally. In the tyi^e they are colorless. 

 There are two types of neuropodials which are the extremes in a series in the 

 parapodia of the middle region. The most dorsal setae are longer and pro- 

 portionately more slender; the distal pectinate division is longer and more 

 slender, from the thickened proximal end narrowing to a long and slender tip. 

 The more ventral, shorter, setae have the heads or pectinate division propor- 

 tionately stouter and shorter, these curving moderately, the concavity on the 

 non-pectinate side. The tip is bifurcate, the principal tooth short and stout, 

 convex on one side, opposite the pectinae; the minor tooth is much smaller, 

 acute, curving a httle away from the principal one. In going caudad the setae 

 become shorter and stouter, the pectinate terminal division being markedly 

 proportionately stouter and shorter. Cephalad the setae become of the more 

 slender type. (Plate 5, fig. 7-9). 



The elytra are small as usual, leaving much of the dorsum uncovered. 

 Each is thin, transparent, wholly smooth and subovate (anterior) or more 

 conmaonly subelhptic in outUne. (Plate 5, fig. 5, 6). They decrease m size 

 caudad. The precise number could not be determined with entue certainty 

 but is either twenty-seven pau's or very near that number. 



Locality. Off Mexico. Sta. 3424 (lat. 21° 15' N., long. 106° 23' W.). 

 Depth, 676 fms. Bottom, grey sand with black specks. Bottom temp., 38° F. 

 18 April, 1891. One specimen. The specimen unfortunately seems at some 

 time to have been dry. 



In comparison with L. irregularis Ehlers (Zool. jahrb. Suppl., 1901, 2, p. 

 255) from the south Chilean coast, this is seen to be a much shorter form with 

 but fifty-six parapodia bearing somites as against eighty-seven in that species. 

 The parapodia are proportionately much longer. The elytra are colorless, thin 

 and transparent whereas in irregularis they are thick and dark grey or black. 

 The tentacles are more slenderly and uniformly acimiinate as are also the palpi, 

 not abruptly narrowed to the slender tip. The setae are much more numerous 

 and differ in details of structure. 



