PLATE X. 



PIU 



l.J-Transparent cross, with tubular canals running through the arms 

 and united by a central ring, — a structure resembling an object 

 fio-ured in Professor W. J. Bailey's "Microscopic forms in the 

 Sea of Kamschatka," under the name " Spongolithes orthogona," 

 but which he says he has referred with some hesitation to 

 Spongolithis. Measures .01125 high, .008 broad, with a slightly 

 warted or rugose surface. 



2. All Eucyrtidium form bearing tubular spinous projections, arranged 



in the pattern of the perforations m Eucyrtidium elegans; 

 appears to be enclosed in a transparent egg-shaped sheath or 

 envelope, .00362 long — Lithobotrys adspersa, Ehr. Mik. Taf. 

 XXXVI, fit;. 5, has the appearance of a wing or fin extending, 

 round the object in a somewhat similar way, and so iius 'Jarpo- 

 canium solitarium, Taf. XXII, fig. 28. This specimen is in 

 iSlide No. 611 Springfield, Barbados. 



g. Eucyrtidium (?) elegans, in an imconstricted state, .004 long, .0012 



broad • 2-3 rows of nearly equi-distant perforations ; from Chim- 

 borazo, Barbados. 



4._APodocvrtis (?) mitraor iiapalis, var. (?) the lower part devoid 

 of perforations, and with a thickening of the silex round the 

 boundary of the plam part, — two spines from the apex. 



5._Fodocyrtis'papalis, Ehr. Mik. XXXVI, 23, .00687 high, .00375 

 broad. In numerous specimens the outline of the base varies 

 considerably, Ijut there always appears to be an internal ring 



or ledge. 



