96 SMITHSONIAN MISCELLANEOUS COLLECTIONS 



150. MACROPHTHALMUS SERRATUS White 



Pi, ATE XIII, Fig. 3 

 Macrophthahniis serratus White, Voy. Samarang, Crust., p. 51. 



Our species agrees pretty well with White's description of his M^ 

 serratus^ but as no figure of that species is given and as the descrip- 

 tion itself is short and unsatisfactory we do not consider the identifi- 

 cation as certain. 



In our specimens the carapax is broader posteriorly than at the 

 angles of the orbits. Proportion of length to breadth, i : 1.4. Sur- 

 face granulose, with the exception of a smooth space at the middle 

 of the gastric region. Lateral margin quadridentate, the small 

 fourth or posterior tooth being only the anterior extremity of a 

 slight crest which margins the posterior third of the side. Ambula- 

 tory feet not pectinated, but villous, the hair short and soft. It dif- 

 fers from M. simplicipes in the want of tubercles on the carapax, and 

 from M. aifinis in being narrower anteriorly and having a more 

 strongly dentate margin. Living specimens were brownish or dust- 

 colored above, white below. The dimensions of a male are : Length 

 of carapax, 0.85; breadth, 1.19 inches. 



A small Lepas is found in considerable numbers upon the feet of 

 this species. 



It was dredged in abundance on muddy bottoms, in 4 to 10 fath- 

 oms, in and near the harbor of Hongkong. 



151. MACROPHTHALMUS DENTATUS Stimpson 



Plate XIII, Fig. i 



Macrophthabnus dentatus Stimpson, Proc. Acad. Nat. Sci. Phila.. x, p. 97 

 [43], 1858. 



Carapax broad, length to breadth as i : 1.67. Upper surface naked, 

 uneven, but smooth and glossy, except toward the postero-lateral 

 angle, where there are two slightly raised, plicated longitudinal ridges.. 

 Lateral margin armed with teeth nearly throughout its length ; teeth 

 four in number, small, except the anterior one, which forms the angle 

 of the orbit and is long and acute. Front very narrow. Eyes long,, 

 but falling short of the extremity of the orbital angle. Chelipeds 

 angular, but everywhere smooth and glossy ; fingers short ; immova- 

 ble finger very short, armed within by a large triangular tooth at the 

 middle, which bears a denticle on its anterior side; dactylus with a 

 tooth at the base and another small but well-separated one near the 



