4 PROCEEDINGS OF THE NATIONAL MUSEUM vol. m 



Table 1. — Comparative measurements (in microns) of 11 specimens of Loxosomella 

 bimaculata, new species (PR 11/3 = newly freed bud from PR IV/4; PR 11/13 = 



holotype) 



take a small spot of pigment "along" that, in a certain state, stretches 

 sideward, assumes a dumb-bell shape, and divides, thus again 

 covering two symmetrical swellings that develop simultaneously (fig. 

 3). This happens even before tentacles become apparent. The swellings 

 contain a granular substance that stains uniformly blue in Azocarmin- 

 Pasini. The pigment is not fluorescent; it bleaches in acidified potas- 

 sium permanganate and stains in acidified solution of toluidin blue. 

 It seems to be melanin, since it also reacts positively when treated 

 with Lillie's ferrous ion. (Techniques after Barka and Anderson, 

 1965.) 



Discussion.- — Because of its morphological appearance, this 

 species must be very close to Loxosomella cricketae Nielsen (1966a). 

 The conspicuous tentacular membrane particularly can not be found 

 in any other loxosomatid. Loxosomella bimaculata is much smaller 

 and has well-developed wings on the foot. Since the anterolateral 

 swellings are pigmented so characteristically and passed on to the buds, 

 I do not believe they are only seasonal appearances or products of 

 certain developmental stages. Whether or not "a pan of red swellings 

 at the anterior part of the hyposphere" (Nielsen, 1966a, p. 256) on 

 larvae of L. cricketae (observed in November) are homologous remains 

 to be proven. 



Loxosomella parguerensis, new species 



Figures 4-6 



Holotype.— USNM 11932 (slide mount). 



Paratypes. — USNM 11932 (on same slide as holotype), USNM 

 11933 (slide), USNM 11931 (alcohol). 



Locality. — Together with L. bimaculata, on the same specimen of 

 Tedania ignis from pilings (just below low-tide level) of the south 



