Messrs. Woodward and Barrett on the genus Synapta. 219 



in the field of the inch object-glass (| inch diameter) ; and the an- 

 chors are more than half as long again as the plates *. 



Mr. Cocks, who met with Synapta inhcerens on the coast of Corn- 

 wall, regarded it as a variety of S. digit ata. He describes it as 

 having ** 13 digitated pinnse on each tentaculum. Length of speci- 

 mens procured from 1 to 2\ inches by yV^h to ^th of an inch. Found 

 in hard and stony soil ; Helford, scarce ; Falmouth, very rare. I 

 have kept them alive for months in sea-water procured from Helford 

 or Gwyllyn-vase, but they invariably broke into fragments as soon 

 as water from Green Bank was thrown into the glass." 



Lastly, two small specimens were dredged by Mr. MacAndrew in 

 Bantry Bay, in August 1857. 



Synapta bidentata, W. & B. 



The new species which we have now to describe was presented to 

 the Zoological Museum of the Cambridge University by the Rev. 

 G. Vachell, who brought it from China. There is also a specimen 

 in the British Museum presented by Mr. Reeve. In its contracted 

 state it measures only 2 inches in length and 5 lines in diameter. 

 The skin is unusually thick, much corrugated transversely, and 

 thrown into five deep longitudinal folds. It is almost devoid of 

 colour, but the ventral band may be distinguished by its breadth, 

 the lateral being rather less wide, and the dorsal muscles narrower 

 still. The twelve tentacles are each furnished with four lobed digits 

 surrounded with a sheath. 



The anchors are short and stout (rather shorter than those of S. 

 digitatd), with straight projecting "beams" ; the flukes are smooth 

 and bifid. From 50 to 70 occur within a radius of ^th of an inch. 



The anchor-plates are obovate, truncated at the articular end, and 

 pierced by very numerous circular holes, which diminish in size from 

 the centre to the circumference. The margin is never completed 

 (so far as we have seen), but the boundary of the external perfora- 

 tions is broken, like that of a w^ire-gauge. 



The miliary granules are rather large, very numerous, and resem- 

 ble cruciform fragments of the anchor-plates. Near the bases of 

 the tentacles they become still more numerous, larger, and more 

 complicated. 



Monstrosities. — As might be expected of minute organs indefi- 

 nitely multiplied, monstrosities are not unfrequent. Mr. Hislop has 

 a slide of Synapta vittata in which two of the anchors have double 

 shanks, and we have seen S. bidentata with three flukes. 



Genus Chiridota, Esch. 



This genus was proposed by Eschscholtz at the same time with 

 Synapta. It was defined as having digitate tentacles, whilst Syn- 

 apta had pinnate tentacles, — an unfortunate definition, as all the 

 species figured in the * Zool. Atlas ' are represented with pinnate 

 tentacles ; and of the two other examples of Chiridota quoted, viz. 



* *• Slides " of this specimen are in many cabinets, with a red label, but with 

 no specific name or locality. 



