REVISION OF RECENT BAIRDIIDAE 43 



ation into transparent and opaque areas, and their subdivided muscle 

 scars, sometimes rather macrocypridid in aspect, when combined with 

 their very different ecologic requirements, present a rather ahen aspect. 

 When better material is available, it is certain that they will be more 

 comfortably accommodated in a separate genus. 



Paranesidea fracticorallicola, new species 



Figures 16-18; Plate 1: figures 5, 6 



Etymology. — hsitinfr actus, hToken-\-corallum, coral+-co/a, dweller. 



Type specimens. — Adult male holotype USNM 121287; allotype 

 USNM 121288; paratypes USNM 121289-121293. 



Type locality. — Nosy B6, Madagascar, sample 196 (washings of 

 Enteromorpha-like alga at low tide level of the beach at Ambariobe). 



Diagnosis. — Carapace robust, inflated, left valve in lateral view 

 with broadly arched dorsal margin, greatest height located slightly 

 behind midlength, greatest thickness located near venter, surface 

 very gently pitted. 



Copulatory organ with median and terminal lobes inseparable, 

 apparently fused; with stout curved conical process arising laterally 

 at their junction; terminal lobe smooth, pigmented, and mushroom- 

 shaped distally; copulatory tube thin and straight, ending in short 

 loop. 



Material. — Nosy Be; 48 living specimens, 400 subfossil specimens. 

 Anton Bruun station 412C, one living male. 



Habitat. — Nosy Be; moderately common on calcareous and non- 

 calcareous algae and accumulations of dead coral fragments near low 

 tide level on the back-reef platform and lower beach. 



Subfossil distribution. — Nosy Be; abundantly distributed in 

 sands and sandy muds from beaches, reefs, and offshore depths to 

 30 m. 



Dimensions.— Adult male USNM 121287, left valve, length 

 0.92 mm, height 0.54 mm; right valve, length 0.92 mm, height 

 0.46 mm. 



Adult female USNM 121288, left valve, length 1.02 mm, height 

 0.62 mm; right valve, length 1.02 mm, height 0.56 mm. 



Paranesidea harpago (Kornicker), 1961 



Figure 19 

 Bairdia harpago Kornicker, 1961, p. 63, pi. 1: fig. la-b; fig. 7a-j. 



Material. — Three living and recently dead adult males from 

 Bahamas samples 132, 201, and Andros 110; 4 adult females. 



Distribution. — Bahamas. 



Dimensions.— Adult male USNM 121294, left valve, length 

 1.07 mm, height 0.74 mm; right valve, length 1.05 mm, height 0.64 mm. 



