516 " THETIS " SCIENTIFIC RESULTS. 



of the stem, three or four being most common, while the inter- 

 mediate portion is smooth, or bears a set of fairly definite rings, 

 •or is indefinitely corrugated after the manner of the stem of the 

 •common European Canipa^itdaria voluhilis. Upon the stems are 

 placed firmly the exceedingly long and slender hydrothecee, four 

 times as long as broad, almost cylindrical in shape, but in the 

 proximal half tapering gradually to the base. A weakly developed 

 •diaphragm surrounds the wall a short distance from the base and 

 the margin is cut into ten or eleven long bub rounded teeth, 

 which are separated by deep, semicircular embayments. Rarely 

 the margin of a hydrotheca is duplicated. 



Scarcely a trace of ccenosarc remained, and no gonosome 

 was |)resent. 



Dimensions. — 



Stolon, diameter ... 0"04-0'06 mm. 



Stalk, length 0-38-M7 „ 



„ diameter 0-048-006 „ 



Hydrotheca, length 0-66-0-87 „ 



,, diameter at mouth... 0*19-025 ,, 



Remarks. — These specimens are without doubt identical with 

 Marktanner's specimens, from which they difi'er only in having 

 somewhat larger hydrothecae, with ten or eleven instead of twelve 

 teeth. On the other hand, they are smaller than Warren's 

 specimens, and differ moreover in having the ringing of the stem 

 kss definite, and in lacking a " terminal small spherule." The 

 possession of such a spherule may on occasion be a good specific 

 ■character, but the fact that in Warren's examples it is " very 

 variable in size," and can scarcely be distinguished in his 

 figures, seems to show that its occurrence thei'e is scarcely so 

 significant. 



That Warren, ignorant of Marktanner's species, should have 

 ■elected to call his specimens elongata also, is a coincidence witness- 

 ing to the distinctive character which rests in the long, narrow 

 hydrothecge. 



Locality. — Creeping on a Polyzoon, from off the coast of New 

 South Wales; March, 1898 ; very rare. 



The species is new to the fauna of Australia. Previous records 

 are from Auckland, New Zealand (Marktanner), and Bird Island, 

 Algoa Bay, 40 fathoms (Warren). 



HEBELLA CALOARATA {A. Agassiz). 



Lafo'ea calcarata, A. Agassiz, Mem. Mus. Comp. Zool. Harvard, 

 i., 1865, p. 122, fig. 190. Id., Billard, Exped. Sci. " Tra- 

 vailleur" et "Talisman," viii., 1907, p. 174. 



