162 CEYLON PEARL OYSTER REPORT. 



are about half as long again. There is a slight difference in the shape of the body, 

 the specimens from Ceylon taper more towards the oral pole. The position of the 

 tentacular sheath is identical and so also is its sheath opening. As the chief 

 difference lies in the length of the costse, I hesitate to add a new species to the genus, 

 but prefer to mark the difference by establishing a new variety. 

 The " Siboga" specimens were obtained in the Malay Archipelago. 



Order: BEftOIDEA, Lesson. 



Family: BEROLLLE, Eschscholtz, 1829. 



Beroe, P. Browne, 1756. 



Beroe flemingi (Eschscholtz), 1829. 



Pandora flemingii, Eschscholtz (1829, p. 39, taf. ii., fig. 7). 



Beroe pandora, Moser (1903, p. 23, taf. ii., figs. 8 and 9; taf. iii., figs. 9 and 10). 



There are about a dozen specimens in the collection, four of which are in fair 

 condition and the others in fragments. 



Description. The body is conical, compressed in the funnel (transverse) plane, a 

 little longer than wide, and rounded at the aboral end. The mouth is wide and has 

 a fairly thin margin. The costse are of unequal length ; the sub-transversal costse 

 are about twice or nearly twice as long as the sub-ventral costse. The meridional 

 canals do not unite with the stomodseal canals. The lateral canals of the meridional 

 canals meander without uniting in the smaller specimens, while in the larger 

 specimens they unite with those from the adjacent meridional canals, forming a coarse 

 irregular network in the outer wall of the body. Short blind canals also proceed 

 from the circular canal around the mouth. The meridional canals on their outer 

 surface are sparsely sprinkled with minute reddish-brown spots of pigment. The 

 gonads are along the walls of the meridional canals, male and female on opposite sides 

 of the canals. 



Size: 8 millims. long and 6 millims. wide, 10 millims. long and 10 millims. wide, 

 1 2 millims. long and 8 millims. wide. Larger specimens broken into fragments. 



Locality: Off Mutwal Island, March 19, twelve specimens; Galle Bay, July 15, 

 one specimen. 



Distribution : N. Pacific, east of Japan. Malay Archipelago. 



Miss MosKR,in her 'Report on the Ctenophora of the "Siboga" Expedition,' has revised 

 the Pleurobrachiidse and Beroidas, and has given a useful key for the identification of 

 the species. I have tried to identify these specimens with the aid of the key, but 

 remain somewhat doubtful about the result. The difficulty of the identification is no 

 doubt increased by my want of experience in the group and by the fact that the best 

 specimens are early stages. Taking the unequal length of the costa? and the absence 



