590 Canon A. M. Norman — Notes on the 



distinct calcareous margin, margin of area in living speci- 

 mens porcelain-white ; surmounted by al)out fourteen to 

 sixteen spines, which are short, slender, and almost upright, 

 very easily abraded. Ooecium globose, porcellanous; either 

 smooth (as in Smitt's figure) or having a raised pointed 

 arch in front (somewhat as in M. aurita), caused by the 

 incorporation of two of the spines into the front wall of the 

 ooecium. Avicularia, if any, unknown. 



As compared with its close ally, C. craticula, the zooecia 

 are larger (from the same district), the spines more slender 

 and nearly upright, the ooecium without the rib, and avicu- 

 laria are (apparently) altogether absent. 



A peculiarity in this species is its appearance when the 

 spines are all abraded; the membranous front wall appears 

 thickened, and has a yellow and waxy appearance. It might 

 be supposed to be chitinous, but it is dissolved away at once 

 in acid, and only the primitive membrane remains. On the 

 other hand, it is not destroyed by liquor potassse, and thus 

 it would appear that the strengthening material is calcareous. 



Thirty-hve miles off Cape Rozier, Gulf of St. Lawrence 

 [Whiteaves, after whom I name the species) ; off Holstein- 

 borg, Greenland, 57 fathoms, 'Valorous,^ 1875 ; Spitsbergen 

 {Smitt, as " M. lineal a "). 



The species perhaps comes nearest to M. dlscreta, Hincks, 

 but this Arctic form certainly is not remarkable for the 

 margin being "cut into lobes ^' nor do the spines ''incline 

 inwards. ^^ 



36. Callopora Sophies, Busk. 



? 1851. JReptoJlustrma arctica, d'Orbigny, Palseont. Frau^., Terr. Cret. 



vol. V. Bryozoaires, p. 582. 

 1855. Memhmnipora Sophi<s, Busk, Quart. Journ. Micr. Sci. vol. iii. 



p. 255, pi. i. fig. 7. 

 1884. Membranipora Sophies, form matura, Hiucks, " Polyzoa Queen 



Charlotte Islands,'' Ann. & Mag. Nat. Hist. ser. 5, vol. x. p. 9 



(separate copy). 

 1886. Membranipora arctica, Lorenz, Bryoz. Jan Mayen, p. 8, pi. vii. 



fig. 1 (separate copy). 

 1900. Membranipora arctica, Waters, " Bryozoa from Franz- Josef 



Land," Journ. Linn. Soc, Zool. vol. xxviii. p. 60. 



There are commonly two and sometimes three pairs of 

 lateral spines, sometimes none are present. The lateral 

 avicularia have the mandible pointing upivards and imvards. 

 The ooecium ordinarily bears a semicircular rib (see Busk''s 

 orioinal figure, and Smitt, fig. 24), but sometimes a pair of 

 spines being taken into the front wall it presents an acute- 

 angled rib instead. In the space between the zooecia there 



