2. CRISTA. 9 



the upper end, composed of 8-10 pairs of cells (lG-:i()). Surface 

 dull white, slightly punctured." 



Crisia attenuata, Heller, I. c. p. 117, pi. iv. figs. 1, 2. 



Hab. Adriatic (Lesina). 



20. Crisia recurva, Heller. 



"Delicate, ranch branched; branches slender, covered with nu- 

 merous white points ; cells cylindrical, alternate, in the first two 

 thirds straight and closely connate, in the last third free and curved 

 outwards at almost a right angle ; aperture round ; internode 

 usually formed of four pairs of cells. Ovicells rather large, sub- 

 globular, [axillary,] with white punctures." 



Crisia recurva, Heller, I.e. p. 118, pi. iv. figs. 3, 4. 



Hah. Adriatic (Lesina). 



21. Crisia setosa, M'Gilliv. 



" Cells 6-10 in an internode, closely adnate, upper extremity 

 usually free for a very small extent; mouth circular, entire ; cell pro- 

 longed outside the mouth into a stout projection, to which is articu- 

 lated a long, hollow, calcareous spine ; surface finely and minutely 

 granular ; branches usually given off between the first and second 

 pair of cells. Joints brown." 



Crisia setosa, M'Gilliv. Australian Pulyzoa, p. 16. 



Hab. Australia. 



22. Crisia biciliata, M'Gilliv. 



Cells two in an internode ; outer extremity free for a short dis- 

 tance ; mouth circular ; from the outside of each cell arise two long, 

 hollow, jointed, filiform processes. Surface granular. Joints light 

 brown or white. 



Crisia biciliata, 3I'Gilliv. I. c. p. 16. 



Differs^ according to Mr. M'Gillivray, " from GrisicUa edward- 

 siana, D'Orb." (which, as he states, occurs in Australia), " in the pre- 

 sence of two long jointed cilia on each cell, there being but one in 

 C. edwardsiana .... in which species also," he remai'ks, 

 " the cells are much more produced and the cilia are situated much 

 further down the back of the cells." The joints, moreover, in C. 

 edwardsiana are black. 



23. Crisia producta, Smitt. 



Zoooecia 1-4: in each internode, disposed very irregularly, free 

 for more than half their length ; free portion very much produced, 

 slightly curved outwards and forwards, cylindrical ; aperture orbi- 



B 



