428 SIGALION MATHILDA. 



division is somewhat truncate, sloped from above downwards and inwards, and has a 

 small papilla internal to the bristles, which superiorly are whorled, then finely serrate at 

 the tip. Next follow larger bristles, with the distal end of the shaft curved and spinous. 

 The distal region is segmented, and tapers to a fine bifid point (minute beak). Ventrally 

 is a dense group of similar forms, but without spines at the end of the shafts. They 

 are most slender at the ventral ed^e. 



Synonyms. 



1 830. Sigalion Mathildx, Cuvier. Eegne An., 207. 



,, „ „ Bathke. Fauna Norweg., 151. 



1834. „ „ Aud. and Edwards. AnneL, 105, pi. ii, ff. 1—10. 



1840. > „ „ Grnbe. Actin., Echinod., &c, p. 84. 



1848. ,, „ Gervais. D'Orbignv, Diet. d'Hist. Nat., xi, p. 601. 



1851. „ „ Grube. Earn. d. Ann., p. 38. 



•1855. „ „ Peters. Archiv f. Naturges., vol. xxi, p. 38. 



1857. „ „ Kinberg. Eugen. Eesa, vol. ii, Zool., 2, p. 9. 



1865. „ „ De Quatrefages. Ann., i, p. 279. 



» „ Carringtonii, Carrington. Proceed. Lit. and Philos. Soc. Manchest., vol. iv, p. 179. 



1875. „ Mathildse, Mcintosh. Invert, and Fishes St. Andr., p. 118. 



1876. „ „ idem. Trans. Zool. Soc., vol. ix, p. 408. 

 1884. „ „ Y. Cams. Faun. Medit., p. 204. 



1898. „ squamaium, De St.-Joseph. Ann. d. sc. nat., Zool. (8), vol. v, pp. 239, 241, pi. xiii, ff. 



22—29. 



Habitat. — Generally distributed round the British shores. Of large size and rather 

 abundant between tide-marks in the Channel Islands and at St. Andrews, while those 

 from Shetland are small. Most of the specimens are littoral, generally under stones, 

 though occasionally small pale specimens occur in sand, as at Southport. It extends, 

 however, to some depth in the adjoining waters. It is' occasionally tossed on the sands 

 at St. Andrews in considerable numbers after storms, and is also not uncommon in the 

 stomachs of cod, haddock, and flounders (E. M.). The first two are especially partial 

 to this species. They sometimes take refuge in tubes of Terebella when cast ashore. 

 The species seems to be partial to sand. In the ' Porcupine ' it occurred off the Algerian 

 coast between Capes Falcon and Tenez. 



Head (Plate XXIX, fig. 6) somewhat elongated from before backwards, oblong or 

 cylindrical in outline. The anterior border is truncate, with a slight peak at each end. 

 Behind the latter are two pairs of small black eyes, situated close together on each side 

 of the middle line, the pairs not far apart, The anterior pair are nearer each other and 

 also somewhat larger than the posterior pair. From the elevation of the head they look 

 forward and upward. Posteriorly only a transverse furrow marks the boundary of the 

 head. The head bends downward in front, and has soldered to it the two short and 

 somewhat conical lobes of the first feet, which bear externally (dorsally and ventrally) 

 short subulate cirri, and dorsally and internally a tuft of very slender, tapering bristles, 

 most minutely serrated and directed upwards and inwards. Beneath is the long 

 tapering palpus, the tough cuticle of which is usually thrown into fine transverse 



