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PROCEEDINGS OP THE NATIONAL MUSEUM 



VOL. 77 



the body. The proximal dorsal lobes show each a slight depression 

 near to the frontal margin; on the left one, a circle can be traced. 

 On the ventral surface two depressions are found on the extremities 

 of the caudal and the lateral lobes. 



With other specimens these depressions and lines are missing or 

 differently traced, so that no great importance can be attached to 

 them. 



DUPLORBIS OCARINA, new species 



Several females on Hemiarthrus abdominalis (Kr0yer) on 

 Spirontocaris aircuata Rathbun, Albatross Station 2842, between 



Figures 15-16.- — Duplokbis ocarina, femalei, 15, left 

 SIDE. For a and 6 see text ; for c and d see ex- 

 planation OF Figure 16. 16, transverse section 



THROUGH female CORRESPONDING WITH THE LINE C-d, 



Figure 15 ; schematic. I, intestine ; L, lobe of 

 ovaky ; M, MARSUPIAL POUCH ; O, ovary 



Unalaska and Cook Inlet, Aleutian Islands 54° 15' N., 166° 05' W., 

 July 23, 1888, 72 fathoms; pebbles; of these the largest has been 

 pelected as the holotype (Cat. No. 62734 U.S.N.M.). The species is 

 parasitic in the branchial cavity of Hemiarthrm dbdomincdis 

 Kr0yer. The male is unknown. 



The body consisting of three lobes has the shape of an ocarina, a 

 well-known musical instrument. By means of the lobe correspond- 

 ing with the mouthpiece of that instrument, the animal is attached 

 to its host! At the extremity of this lobe is a little incision corre- 

 sponding to the mouth opening. The surface of the body has a 



