152 



BULLETIN 97, UNITED STATES NATIONAL MUSEUM. 



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$ 



Fig. 93. — IMxnixa 



CH AETOl'TEKANA, 



BizzAKUS Bay. a. 

 Chela of addlt 

 female, x g : 6, 

 chela of auli.t 



MALE, X 4. (AFTEE 



Faxox.) 



Diagnosis. — Carapace uneven. Two short ridges on cardiac region. 



Fingers of male widely gaping. Dactyli of first two legs slightly 



curved, of last two straight. 



Description of male. — Surface densely pubescent and hairy, espe- 

 cially on chelipeds and margins of carapace and legs. Eegions and 

 their subdivisions well limited; subbranchial re- 

 gion advanced, forming a prominent shoulder 

 with granulated edge; lateral angle a right angle; 

 a submarginal groove parallel to posterior and 

 postero-lateral margins; on each side of cardiac 

 region a short sharp ridge arched upward; a few 

 granules on antero-lateral margin; front little 

 advanced, truncate. 



Chelipeds strong, smooth ; palm very wide, con- 

 vex on margins except near base of fixed finger, 

 which is very short, much deflexed, with a strong, 



triangular, prehensile tooth near its base and an obliquely truncate, 



notched tip; dactylus strongly curved, almost vertical and forming 



an oval gape when closed. 

 Dactyli of first two legs slender and slightly curved, of last two, 



stout and nearly straight; first and second legs slender and of nearly 



same size, second reaching to end of propodus of third ; third stout, 



merus about twice as 



long as wide, nearly 



straight above, dis- 



tally narrowed, pos- 

 terior margin, as 



well as that of pro- 



podus, spinulous; 



fourth leg of similar 



build, reaching to 



middle of carpus of 



third. 



Sixth segment of 



abdomen constricted 



at middle, seventh Fio. 94. — Pinmxa chaetopteraxa (5043). a, Odter MAXiL- 



• • 1 LirED OF FEMALE, X 11 ', h, ADDOMEX OF MALE, X G8. 



semicircular. 



Sexual valuation. — Carapace more swollen in female, fingers mod- 

 erately deflexed, not gaping, thumb longer and stouter, a small 

 tooth at each end of truncate extremity, no subbasal tooth, a small 

 tooth on dactylus behind middle. 



Aleasurements. — Male (5043), length of carapace 6.3, width of same 

 14mm. Female (18289), length of carapaceG.3, widthof samel4mm. 



Habitat. — Commensal in tubes of annelids, Amj)hitrite ornata and 

 Chaetopterus pergamentaceus " whose parchment-like sheath, ex- 



