478 TAGE SKOGSBERG 



hyaline .spine. At about half way between and parallel to the posterior margin of the shell 

 and the dorsal half of the spine-bearing list there is a sparse row of about six or seven 

 broad pores; each pore is furnished with a freely projecting hyaline peg (the shape of these 

 pegs could not be observed with certainty). Behind the dorsal half of the posterior medial 

 row of bristles is seen in fig. 3 a double line running transversely over the shell; this 

 corresponds to a sharp edge. The part between this and the posterior margin of the shell 

 is situated rather considerably more laterally and thus, when it is looked at through the 

 microscope from inside, rather considerably deeper than the part situated within the double 

 line. This character is in most cases only distinctly developed on the right valve, as on 

 the left valve this ridge is so near the margin of the shell that it often seems quite to 

 coincide with the latter. 



First antenna (fig. 4): — This has seven joints, the third and fourth joints are 

 free from each other. These two joints together form a joint that is somewhat shorter than it 

 is high and also somewhat shorter than the total length of the fifth and sixth joints. The distal 

 boundary of the fourth joint is rather strongly concave. The anterior bristle of the second joint is 

 somewhat longer than the anterior side of this joint. The third joint has six anterior bristles, 

 of which nos. 5 and 6 are fixed at the side of one another. Nos. 1, 2 and 4 of these bristles are 

 armed ventrally with long, stiff secondary bristles, the others have short hairs. The longer 

 of the two posterior distal bristles on the fourth joint is not quite as long as the the fifth joint. 

 Sensory bristle of the fifth joint: The stem is about as long as the total length of the third to 

 the fifth joints; it is furnished with seven sensorial filaments. The end joint has seven bristles, 

 the d-bristle is developed as in the preceding species but unlike all the other species of this genus 

 in which this character is known. The a-claw is somewhat longer than the total length of the 

 anterior side of the two next distal joints and is exceedingly finely and weakly pectinated proximo- 

 anteriorly. The f-bristle has four or five sensorial filaments. The c- and g-bristles have a some- 

 what varying number of sensorial filaments: on the t}^3e-specimen the c-bristle had nine, the 

 g-bristle seven on the antenna of the right side; on the antenna of the left side the c-bristle 

 had seven, the g-bristle eight filaments; on two other specimens both these bristles had seven 

 sensorial filaments on both the right and the left antennae. The d-bristle is somewhat more 

 slender but rather slightly shorter than the e-bristle. Pilosity: The first and second joints have 

 niimerous groups of stiff, fine hairs on the greater part of both the inside and the outside (not 

 drawn in the figure); there never seem, however, to be any such bristles on the anterior distal 

 part of the inside of the second joint. Distally the second joint has a close row of short, stiff 

 hairs antero-laterally. 



S e c o n d a n t e n n a: — Distally on the inside close to the exopodite the p r o t o- 

 p o d i t e has one very short bristle. The exopodite has four bristles on the end joint; 

 the fourth to the ninth joints of this branch have basal spines. The e n d o p o d i t e is distinctly 

 three-jointed; its end bristle is about as long as the stem (fig. 5). 



Mandible: — Protopodite: Coxale: The scythe-shaped process (fig. 8) : 

 The part situated distally of the main spine grows uniformly and gently narrower in a fine point ; 

 its ventral edge is even, almost straight or even slightly concave. The distance from the point 



