304 
NATJTILOIDEA. 
Cyrtoceras (Meloceras) clathratum, Foord. 
? 1876. Cyrtoceras, sp., Tromelin & Lebesconte, Assoc. Fran^. pour 
I’avancement des Sciences, (Nantes), Tabl. D. No. 25. 
Sp. Char. Shell slightly and uniformly curved. Transverse sec- 
tion nearly circular. Eate of increase about 1 in 3. Septa and 
siphuncle unknown. Surface ornaments consisting of prominent 
acute annulations, which are somewhat wider apart in the upper 
Fig. 48. 
I 
Cyrtoceras {Meloceras) clathratum. — a, fragment of the shell, natural size ; 
h, portion of the test, greatly enlarged. 
part of the shell than they are in the lower ; their distance 
from each other increasing from about 5 to | of a line ; these are 
crossed by pretty close-set longitudinal ridges (about three in the 
space of 1 line) which form nodes at their junction with the annu- 
lations. Where the test is well preserved, fine, transverse, thread- 
like lines are seen, crossing the ridges and the interspaces ; ten or 
twelve of these lines are contained in' the space of 1 line. 
Remarks. Though some important characters are wanting in our 
knowledge of this species, yet its ornamentation would be quite 
sufficient to distinguish it. Its nearest ally appears to be M. Pan- 
deri, Barr., sp. (pi. clvii.), but the latter expands more slowly, and 
the longitudinal ridges of its test are very feebly developed, while 
the annulations are stronget than those of the present species, fur- 
thermore the fine transverse lines are wanting in M. Panderi. Both 
belong to about the same horizon. 
Horizon. Calcaires ampeliteux (= Third Fauna of Barrande). 
Locality. Feuguerolles (Calvados), France. 
Eepresented in the Collection by three specimens. 
