ECHINOIDEA 



335 



scarcely occurs within tide limits, as does that species. Develop- 

 ment unknown. It appears that the breeding season is in the 

 early summer months. 



Fig. 196. — Proximal end of posterior interambulacrum and the adjoining 

 ambiilacral plates of EcMnocardium pennatifidum (1) and Ech. flaves- 

 cens (2). x 3. (From Danmark's Fauna.) 



tii-a, Ambulacral plates Nos. 1-3 ; 1, Labrum ; p, Pores of tube-feet ; pi, Plastron 



or sternum. 



Monstrous specimens of this species, often of quite fantastical 

 shapes, occur not very rarely, e.g. in Skagerrack (cf . Brissopsis 

 lyrifera). 



In British seas this species apparently occurs all round the 

 coasts, in places very common, though scarcely so much so as 



12 3 



Fig. 197. — Valves of triphyllous pedicellarias of EcMnocardium cordatmn (1), 

 Ech. fiavescens (2), and Ech. pennatifidum (3). x 200. (After Th. 

 Mortensen, '' Ingolf"' Ech., ii.) 



the preceding species, and usually not together with that species. 

 It is elsewhere distributed from Finmark and Iceland to the 

 Azores and the Mediterranean. Not known from Greenland, and 

 the record of its occurrence on the east coast of N. America 

 needs verification. Bathymetrical distribution ca. 5-325 m. 



3. EcMnocardium pennatifidum la^OTman. (Fig. 198.) 



(Sjrn. Amphidetus gibbosus Barrett ; non Agass.^) 



Frontal ambulacrum not sunk, anterior end of test rounded, 

 at most with a very slight indication of a notch. Pores of frontal 



^ The Amphidetus gibbosus Agass., with which the present species was 

 identified by Barrett, who first discovered it, is a synonym of Echinocard. 

 mediterraneutyi. 



