A. E. Verrill — North Amet'ican Ophmroidea. 313 



U.—Amphiodia Verrill, 1899a. (See p. 316.)* 



Oral papillae three, rarely four, subeqiial, or the outer one is 

 smallest, forming a regular series on the side of the jaw. Arm- 

 spines three, rarely four. No distal oral tentacle-scale. 



B. — Disk-scales naked. 



c. — Two tentacle-scales. 



d. — Radial shields rather wide, in contact at least distally. 



A. Riisei (Ltk.) Ver. Oral shield elongate ; adorals small, trigonal. 



A. atra (Stimp.) Ver. Oral shield pelecoidal ; adorals lunate, 

 narrow. (Sometimes has four oral papillae and four arm-spines.) 



A. planispina (V. Mart.) Ver. Oral shield ovate, broadest prox- 

 imally ; adorals narrow, lunate. Brazil. 



cc. — One tentacle-scale. Radial shields long and narrow, largely 

 in contact. 

 e. — Disk with scales on the under side ; on the upper side larger 

 scales form a rosette. Arm-plates separated above and 

 below. Oral shield obovate, smallest proximally. Adoral 

 shield large, trigonal. 



A. pulchella (Lym. '69) Ver. • Florida. 



ee. — Disk without scales below ; no rosette above. Oral shield 

 "spade-shape," with a distal lobe. Adoral shield broad 

 triangular. 



A. repens (Lym. '75) Ver. Florida. 



BB. — Some of the disk-scales, near the margin or beneath, bear 

 small spinules, or granules, or both.f 



A. LutJceni (Ljng.) Ver. West Indies, 



" Amphiodia is represented among extralimital species by a large series. 

 Some are as follows. From west coast of America, five: A. Barbarce (Lym.), A. 

 grisea (Lj.), A. urtica (Lym.), A. occidentalis (Lym.), A. Chilensis (M. & Tr.), A. 

 Orstedii (Ltk.), A. antarctica (Ljng.), Magellan Str. ; A. fissa (Ltk.), Amoor ; 

 from the Indo-Pacific A. ochroleuca (Brock), A. olivacea (Brock), A. im2Jyessa 

 (Ljng.), A. Andi-ece (Ltk.), A. Icevis (Lym.); from South Africa, A. gibbosa (Ljng.), 

 A. integra (Ljng.) 



\ AmphiplioUs Lutkeni Ljng. and Ophiocnida Loveni (Ljng., Lym.) would, 

 perhaps, go here, but they are so closely related to the type of Ophiocnida that 

 I have referred to them under that genus (see p. 816). 



