1904.] ASELL0TA-C4R0UP Ok' CRUSTACEANS. 331 



Fig. 2 k. Left pleopod of second pair of the same male, fioui in front ; X 51. Th« 



muscles in the sympod are seen. 

 2 ?. Left pleopod of third pair of the same male, from in front ; X 51. 

 2 7.:. Left pleopod of fourth pair of the same male, from in front ; X 51. 

 2 I. Left pleopod of fifth pair of the same male, from in front ; X 51. 

 2 m. First pair of pleopoda, constitiiting a small operculmn, of an adult female, 



from in front ; X 51. 



2 n. Left pleopod of third pair of the same female, from m front ; X 51. 



Fig. 3. Stenetrimn antlllense, sp. n. (p. 326). 

 Fig. 3rt. Left mandible of a male, from below; X 49. 



3 b. Distal part of the mandible shown in fig. 3«, from below ; X 125. _ 

 3 c. Distal part of right mandible of the same male, from below ; X 125. 

 3 d. Hypopharynx (paragnatha) of the same male, from below ; X 49. 



3 e. Left maxillula of the same male, from below ; X 49. 



3/ Distal part of the lobe from third joint of the maxillula shown m fag. 3 «; 



from below ; X 185. : 



3^. Left maxilla of the same male, from below ; X 49. ^ 



3 h. Left maxilliped of the same male, from below ; X 49. 

 3 i. Distal portion of first left thoracic leg of an immature female, from thft 



exterior side ; X 53. 



Plate XXI. 

 Fig. 1 a. Stenetrimn antillense, sp. n. (continued) (p. 326). 

 Pig. 1 a. Adult male, from above ; X 9. Several appendages omitted. 

 1 h. Head of the adult male shown in fig. 1 a, from above ; X 24. 

 1 c. First left thoracic leg of the adult male shown in fig. 1 a, from the exterior 



side ; X 16. , , • , i. 



Irf. Major part of fifth joint and prehensile hand of first right thoracic leg ot 



another male, from the exterior side ; X 28. 



1 e. Abdomen of an immature female, from above ; X 36. 



Fig. 2. Stenetrium siamense, sp. n. (p. 327). 



Fig. 2 a. Head of an adult male, from above; X 33, ., zj. 



2 b. First right thoracic leg of an adult male, from the exterior side (from 



behind) ; X 33. o , ^ ■ 



2 c. First right thoracic leg of a not quite full-grown female, from the exterior 



side; X 33. ,. , . ■ 



2 d. Palmar edge and " claw " of the leg shown in fig. 2 c, from the exterior 



side; X 86. 

 2 e. Abdomen of an adult male, from above; X 28. Uropoda wanting. 

 2 /. First pair of pleopoda of an adult male, from in front ; X 50. m., muscle 



to the ramus. ^ 



2 (/. Second left pleopod of an adult male, from in front ; X 50. 

 ■I'li. Distal part of the sympod, endopod, e»., and exopod, eu:., of the pleopod 



shown in fig. 2ff, from in front ; X 95. In the sympod the muscles for 



the movement of both rami are shown. ■ e u 



2 i. First pair of pleopoda, constituting a small operculum, of a not quite full- 



gi-own female, from in front ; X 50. 



Figs. 3-6. Farts of various Asellota. 

 Fig. 3. Distal part of sympod with both rami of second left pleopod of the male of 

 Asellus aquaticns L., from in front ; X 54 (p. 306). Three muscles to the 

 rami are shown in the sympod ; in the first joint of the eudopod a muscle to 

 the second pint is seen,' in the distal joint of the exopod a muscle producing 

 the movement of this joint is plainly visible. The dotted line on the distal 

 joint of the endopod indicates the outline of the sac within. 



4. First pair of pleopoda and second right pleopod of a male of an undescribed 



form rather allied to lanira, seen from in front ; X 43 (p. 309). r., ramus, 

 and s., sympod of first left pleopod ; t., second pleopod, with the short hook- 

 shaped exopod, while the elongate endopod has been omitted. 



5. First pair of pleopoda of a male of lanira maculosa Leach, from m front ; 



X 32 (p. 309). r., ramus; ,9., sympod. 



6. Distal inner part of left second pleopod of a male of Eurycope gigantea 



G. 0. Sars, from in front ; X 12. b. (p. 309), basal joint of endopod divided 

 into two parts or joints ; c. (p. 309), cavity within the distal joint of th» 

 endopod; d. (p. 312), duct from this cavity; e.v., two-jointed exopod. 



