BY J. DOUGLAS-OGILBY. 271 



entirely hidden beneath the skin, and four rays. The disk between 

 them is longer than broad: that attached to the coracoids broader 

 than long, and with a small angular cutaneous flap behind ; the 

 hardened epidermis entirely surrounds this disk, and is composed 

 of series of circular plates with a centi-al hollow, much resembling 

 miniature disks ; of these there are about four rows anteriorly 

 and eight rows posteriorly, those on the inner side being always the 

 largest ; on the ventral portion of the disk these plates are arranged 

 in a narrow band, and are very minute in front, but are large and 

 in about seven series on the anterior membranous part of the 

 ventrals, and their outer rays almost to their tips ; the posterior 

 edge of this portion of the disk is without plates, the length taken 

 Tip by the entire sucking apparatus is exactly one-fifth of that of the 

 fish. The vent is situate considerably behind the middle of the 

 fish, and much nearer to the origin of the anal fin than to the 

 posterior margin of the disk. There is a small genital papilla 

 behind the an vis. The coi'acoid flap extends upwards to fully three- 

 fourths of the base of the pectoral, and is joined to the side by a 

 median transverse web. 



Uniform pink, appearing almost transparent when first removed 

 from the water. 



The example from which the description has been drawn up, was 

 taken by the trawl on Shai'k Reef, Port Jackson, upon the 30th of 

 May, and gives the following measurements. 



Total length 



Length of head 



Origin of dorsal to snout 



Origin of dorsal to origin of caudal 



Anus to snout ... 



There are about 10 strongly marked vertical ridges on each side, 

 caused by the contraction of the muscles after death, but not 

 present in the living fish ; owing to this peculiarity, which is 

 common to its congener, Diplocrepis puniceus, Rich., from New 

 Zealand, I have proposed costatus as a suitable specific name for 

 this interesting form. 

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