283 



than in genera, where the main characters are the easily dissolved, 

 calcareous deposits from the skin. Thus it is also erroneous when 

 Théel writes that "The one form passes imperceptibly into the 

 other in such a manner that no special specific characteristics can 

 be drawn up." 



As to the geographical distribution of the genus, we may say 

 that Chiridota is the widest distributed genus of the Synaptidae, 

 though the single species are rather local. Clark states Ch. lœvis 

 (Fabricius) to be a circumpolar species; but on the other hand he 

 says (Apod. Holoth. pag. 29) about the large collection of this species 

 in the United States National Museum, that "the specimens are in 

 a very poor condition", and that "it seems almost certain that there 

 are at least three species included in this mass of material". From 

 what is said above, it seems rather evident that these three species 

 are lœvis, albatrossii and pacifica. 



The hitherto known species of Chiridota may be distinguished 

 as follows: 



1. Miliary granules entirely wanting in the skin, though oval bodies are 



often present in the longitudinal muscles 2 



Miliary granules present in the skin, though in few cases confined 



to the anterior end of the dorsal side 7 



2. Wheel-papillae numerous, more or less uniformly scattered all over 

 the body, not distinctly arranged in longitudinal series... fernandensis 

 Wheel-papillae rather few, usually confined to the dorsal side of body, 

 where they are arranged in more or less irregular rows, one in each 

 interambulacrum 3 



3. Ciliated funnels usually united into stalked clusters, colour greyish, 



size up to 30 cm, boreal discolor 



Ciliated funnels not united into stalked clusters 4 



4. Mid-ventral radial not perforated for the nerve, but notched in the 



anterior margin. Colour reddish pisanii 



Mid-ventral radial perforated for the nerve; colour not reddish, but 

 white, brown or dark purple 5 



5. Colour dark violet or black, size large (ca. 20 cm), ciliated funnels 



small (ca. 0,1 mm), distinctly stalked "cups" nigra 



Colour not dark violet. Ciliated funnels large (up to 1 mm) and not 

 stalked "cups" 6 



6. Ciliated funnels of different shape and size, the largest ca. 1 mm, and 



"french-horn"-shaped carnleyensis 



Ciliated funnels of nearly the same size and shape, not "french-horn"- 

 shaped lœvis 



7. Miliary granules stellate plates marenzelleri 



