FTCOM the MERG-UI archipelago. 



133 



which support the calycles, and annulated above them. Hydrotliecce 

 alternate, borne on short pedicels ringed throughout (about 7-8 

 rings), narrow, contracted at the base, from which point the wall 

 slopes outward for a short distance, so that the lower extremity 

 of the calycle is funnel-shaped, the upper three fourths subcylin- 

 drical (expanding very slightly towards the orifice); the rim cut 

 into 10-16 narrow, rather tall, blunt denticles. 



Gonotliecce springing from the main stem near the base of the 

 pedicels, borne on short ringed stalks, narrow at the base, 

 expanding upwards, truncate at the top. Gonozooids medusi- 

 form. 



Sab. On Nellia oculata, Busk. 



The peculiar form of the lower portion of the calycle is charac- 

 teristic. 



? Obelia biftjrca, n. sp. (Plate XII. fig. 1.) 



Stem simple, straightish, annulated above the pedicels. Hydro- 

 tliecce alternate, of large size, tall, contracted below, expanding 

 gradually towards the oral extremity, at which point they are 

 about three times as wide as at the base, borne on short stalks, 

 annulated throughout and not tapering ; the rim cut into about 

 a dozen (?) broad, bicuspid denticles. Gonotliecce {^). 



Hob. On Nellia oculata. 



In the absence of the reproductive zooids this species is re- 

 ferred provisionally to the genus Obelia. 



In some respects it is allied to O. bicuspidata, Clarke, obtained 

 off Thimble Islands, coast of New England ; but the latter seems 

 to be smaller and of much more delicate habit, the calycles 

 are very slender and lineated longitudinally (8-10 distinct lines 

 extending from the top almost to the base), the pedicels are 

 comparatively long and are represented as tapering upwards, and 

 the stem is compound. 



Campa^ularia, Lamarck (part.). 



Cahpanttlaria rarldentata, Alder. (Plate XII. fig. 5.) 

 Hab. On Nellia oculata. 

 [Great Britain.] 



So far as the calycle is concerned, the Mergui form is not 

 distinguishable from Alder's species. The reproductive capsules 

 were not observed. 



