OPHIUROIDEA 221 



Cape Verdes, 75-80 m. '' Talisman "), is scarcely likely to occur 

 so far north as the British region. It is very easily distinguished 

 from A. squamata by having spines on the disk. 



Key to the species of Amphipholis known from or likely 



to occur in the British seas. 



Arms 5 . . . . . . \. A. squamata (D. Ch.) 



Arms 6 A. Torelli Ljungm. 



1. Amphipholis squamata (D. Chiaje). (Fig. 125.) 

 (Syn. Amphiura squamata (D. Ch.) ; Amphiura, Amphipholis 

 elegans (Leach) ; Amphiura neglecta (Johnston) ; Amphipholis 

 tenera Liitken ; A. lineata Ljungman.) 



Disk covered on both sides by rather small scales, among 

 which the primary plates are scarcely distinguishable. Near 

 the edge usually a sharp Umit between the scales of the dorsal 

 and ventral side. Radial shields small, ca. \ of the disk radius, 

 contiguous throughout their whole length. Dorsal arm plates in 



Fig. 125. — Amphipholis squamata ; part of oral side (1) and of dorsal 

 side (2). X 12. (From Danmark's Fauna.) 



the proximal part of arms broader than long, rounded triangular ; 

 ventral plates mth slightly excavate outer edge, contiguous in 

 proximal part of arm. Four, farther out 3, short, conical arm 

 spines. Two tentacle scales, in distal part of arms only 1 . Mouth 

 shields about rhombic, but somewhat produced imvards. Outer 

 mouth papilla very broad. Colour in life greyish- white or bluish- 

 grey. Reaches only a size of ca. 5 mm. diameter of disk ; 

 arms ca. four times that length. 



The variety tenuispina Ljungman differs from the typical 

 form in having somewhat coarser scales on the dorsal side, 

 there being only 4 scales in a transverse row between two adjoining 

 pairs of radial shields, while in the typical form there are ca. 8 

 scales in a transverse row. The primary plates are more distinct. 



