NEBELLA ACOLLA. 119 



In Sphagnum gathered by Mr. Hopkinson at Capel 

 Curig in June, 1908 [at the source of a stream above 

 Dolgam]. 



Only empty tests, but these very perfect ones, were 

 observed. They were transparent and colourless, and 

 structurally had all the characters of Nebela, leaving 

 no doubt as to that being the genus to which the 

 organism must be referred. At the same time they 

 differed from most other members of the genus in 

 being absolutely without neck. A neck, however 

 short, would have justified a reference of the form to 

 N. flabellulum, though the surfacing plates and their 

 disposition differed totally from what is usually found 

 in that species. The test, moreover, was smaller than 

 that of N. flabellulum. It is to be regretted that no 

 living example could be found. Even the empty tests 

 were scarce. 



14. Nebela dentistoma Penard. 

 (Plate XXVIII, figs. 9-1 1 ; and figs. 97 and 98 in text.) 



Nebela collaris LEIDY (pars) Fresliw. Rhiz. N. Amer. (1879), 

 p. 145, t. xxiv, f. 12. 



Nebela dentistoma PENAKD in Mem. Soc. Geneve, XXXI 

 (1890), 2, p. 162, t. vi, ff. 98-100 ; t. vii, if. 1-5 ; and in 

 Amer. Nat. XXV (1891), pp. 1071, 1074; G. S. WEST in 

 Jrn. Linn. Soc., Zool. XXVIII (1901), p. 322; op. cit. 

 XXIX (1903), p. 114; and in Ann. Scott. Nat. Hist. 1905, 

 p. 92 ; SCHODTEDEN in Ann. Biol. Lacustre, I, 3 (1906), 

 p. 355 (note). 



Nebela crenulata CASH in Tr. Manch. Micr. Soc. 1891 (1892), 

 p. 50, t. ii, f. 18 ; PENAKD in Arch. Sci. nat. (3) XXVIII 

 (1893), p. 182; op. cit. (4) VII (1899), p. 265 etc.; 

 and Faune Rhiz. Lemaii (1902), p. 370, ff. 1-5; AVER- 

 INTZEV in Trudui S.-Peterb. Obshch. XXXVI (1906), 2, 

 p. 247 ; MURRAY in Ann. Scott. Nat. Hist. 1 907, p. 95. 



Test variable, moderately compressed, ovoid to 

 rotund, destitute of a neck, the sides, in broad lateral 

 view, sloping convexly from the arched crown down- 

 wards to the mouth, the margin of which is crenu- 

 late. In its structure very variable ; the external 



