THE FOSSIL STALK-EYED CRUSTACEA 43 



Metabranchial lobe large and dorsally much swollen, separated by a 

 curved, transverse furrow from the mesobranchial lobe Avhich in turn 

 is separated from the hepatic and epibranchial lobes by a furrow 

 subparallel to the other, Epibranchial lobe depressed, hepatic region 

 low; anterior half of the narroAV mesogastric lobe well defined, A 

 shallow furrovv' separates the epigastric lobes. An oblique lobe at 

 inner angle of branchial region. 



Outlines : Margin of front slightly arcuate and unevenly granu- 

 late. A furrow between upper surface of front and of orbit. Outer 

 angle of orbit obtuse, from it the lateral margin is oblique and nearly 

 straight for a ways and ends in a rounded, nonprojecting lobe, which 

 is separated from the next tooth by a closed fissure; three similar 

 acute teeth, two of which are of good size, the last one small and little 

 projecting; it is right angled and has a sharp horny tip. These 

 teeth are perfect only in the Stewart specimen. Of the other speci- 

 mens only two (males out of 2938 and 167) have the last tooth de- 

 veloped (pi. 9, fig. 7). Of the postero-lateral margin that portion 

 bordering the mesobranchial lobe is straight and directed somewhat 

 inward and backward, the margin of the metabranchial lobe is 

 arcuate and curves into the posterior margin, which is slightly 

 arcuate and in the middle nearly straight. 



Appendages : Only a hint is given, in one specimen of No. 167, 

 of the form of the outer maxillipeds; the ischium appears broad 

 and its inner margin strongly curved ; only the outer half of a merus 

 is shown, it is not dilated at the outer angle. The unequal chelipeds 

 are stout, the merus projects little beyond the body, the carpus is 

 rounded and has a bluntly rounded inner angle, perhaps not a tooth ; 

 manus thick, dactylus stout. The separate dactylus, No. 4135, is 

 about 14 mm. long, tip excluded, tapers from a stout base to a slender 

 extremity and has a large, backward-pointing, appressed, basal tooth 

 followed by five smaller low teeth, all rounded. Surface of chelipeds 

 and merus of ambulatory legs granulate. 



Ventral surface : The sternum is very elongate and has a trans- 

 verse furrow between the bases of the maxillipeds and an obtuse 

 iingled and slightly curved furrow between the bases of the chelipeds. 

 Sternum granulate, abdomen of male smooth and coarsely punctate 

 except the first and outer ends of the second and third segments 

 which are granulate. The abdominal segments are all distinct; the 

 first and third are about the same width, the second and third are 

 the same length at the middle, the fourth and fifth a little longer, 

 subequal ; the sixth and seventh still longer and subequal ; the fourth, 

 fifth, and sixth segments taken together are suboblong, narrowing 

 but little, the seventh is subtriangular. about twice as wide as long. 



MeasureTnents. — ^Largest specimen, male No. 4135, length 45 mm,, 

 width 47 mm., merus of second ambulatory leg 26 mm. 



