442 PROCEEDINGS OF THE NATIONAL MUSEUM vol. loa 



is probably in error because he shows two somites for the species on 

 plate 36 (Stebbing, 1913). Caecianiropsis diflPers from Thamhema in 

 having well-developed uropods and in the structure of the male 

 pleopods. The mouthparts are similar. The genus also shows a 

 curious resemblance to llie cave-dwelling fresh-water genus Micro- 

 charon Karaman 1934, one species of which, Duslenia (=Microcharon, 

 personal communication from Dr. Claude Levi) teissieri L6vi (1950, 

 pp. 42-47), lives also in the intertidal on the coast of France, where 

 it was foimd in association with an archiannelid polychaete, Saccocirrus 

 papilloceru^ Bobretzky, and the marine mite Scaptognathus tridens 

 Trouessart. Caecianiropsis differs from Microcharon in the structure 

 of the uropods, male pleopods, and the maxillipeds. It seems likely 

 that Austroniscus ectijormis Vanhoffen (1914, fig. 80) belongs to 

 Caecianiropsis; however, Vanhoffen's specimens seem to be immature 

 and an assignment of that species is uncertain. 



Caecianiropsis f new genus 



Type: Caecianiropsis psammophila, new species. 



Diagnosis: Alaxilliped with two couphng hooks; palp with second 

 and third joints expanded but equaling only 1^2 times the width of 

 endognath. First antenna with peduncle of four joints; flagellum 

 with a few joints. Second antenna about one-half the body length; 

 flagellum multiarticulate. 



Epimera visible in dorsal view on peraeon somites 1-7. Endopodite 

 of uropods exceeding twice the length of exopodite. 



Caecianiropsis psammophila, nevr species 



Figures 1-3 



Holotype: Nonovigerous female, length 1.8 mm, width 0.25 mm. 



Diagnosis: Rostrum with frontal margin convex. First antennal 

 flagellum with only two articles; first article exceeding six times the 

 length of last. Posterolateral borders of pleotelson of male each with 

 1-2 minute spinelike teeth; lateral borders smooth except for many 

 small setae; posterior border uith a distinct median convexity. 

 Endopod of uropod exceeding three times the length of exopod. 

 Each lateral apex of first male pleopods with a small, expanded, 

 apically pointed area. Anterior endopodite branch of second male 

 pleopod coiled, equaling body length when straightened out. 



Character of body: Colorless and eyeless, very much elongated, 

 length exceeding sLx times the width. 



First maxilla: Outer lobe with about 12 denticulate setae at apex; 

 inner lobe with one long seta and numerous fine setae. 



