MEGALOMASTOMA. TOMOCYCLUS. 189 
29. Guildingianum (Cycelostoma) Pfr. I. 134. II. 85. III. 87. — 
Megalomastoma suspensum Guild., Swains. (Pfr. I. 135 not)? — 
Megalommastoma suspensum Piel Cat. p. 120: Guatemala? — 
Habitat ? 
Quid ? 
Megalomastoma. lentilabrum Sow., Pütel Cat. p. 120. — St. 'Thomas. 
XXVII. Tomocyelus Crosse & Fischer, 
.Llesta perforata, turrita truncata; apertura subcircularis, 
parvula; peristoma duplex, internum breviter porrectum, ex- 
ternum late expansum, folaceum, margine supero interrupto, 
peculiariter exciso et cavato. — Operculum circulare, corneum 
sed crassiusculum, arctisprum, antice planiusculum, postice 
medio processu obtuse rotundato munitum, margine anfractuum 
sublamelloso.* (Cr.) 
T'omocyclus *) Crosse & Fisch. in Journ. Conch. XX. 1872. p. 76. 
T'omocyclos (genus Pupineorum) Patel Catal. 1873. p. 17. 120. 
Nonne generi Megalomastomati tamquam sectio subjun- 
gendum genus? 
Species: 
1. T. Gealei Crosse & Fischer. 1 
»l. perforata, turrita, truncata, solidula, parum nitida, 
olivaceo-fulvida; spira elongata, sensim attenuata, apice trun- 
cato; sutura valde impressa; anfr. superstites ( convexi, primi 
2 sublaeves, sequentes costulis arcuatis, subobliquis, tenuibus 
longitudinaliter ornati, ultimus basi funiculato-cariatus, carina 
mox evanescente, solutus, descendens; apertura verticalis, sub- 
circularis, parvula; peristoma liberum, solutum, duplex: in- 
ternum breviter porrectum, externum latissime expansum, folia- 
ceum, intus concavum, album, margine supero ad perforationem 
interrupto, peculiariter exciso, in fossulam peristoma internum 
emarginantem desinente. — Long. 45, diam. maj. 12!/, mill. 
Apertura cum peristomate externo 11 mill. longa, 14 lata, 
intus (perist. excluso) 7 mill. longa, 1 lata.*' (C.) 
*) Tóuoc, frustum resectum; »/x4oc, circulus. 
