394 Prof. Grube on the Annelid Family Maldaniea. 
quently the longer of the posterior segments are very much 
inflated behind by the elevation of the cushions on which the 
uncini are inserted, and may easily be torn away from the fol- 
lowing ones, which commence with a thin part. All the seg- 
ments, however, are not armed with bristles in the same man- 
ner: the buccal segment is quite destitute of bristles, as in the 
Lumbricina ; the three following segments certainly bear sete, 
but only a few uncini, or, instead of these, a pair of spinules, 
slightly bent at the apex; and the terminal segment and also 
usually from one to three (four) of the preceding ones, which 
are much abbreviated, are again destitute of bristles, although 
the latter generally have indications of the cushions in which 
the uncini are elsewhere inserted. In contradiction to other 
recent observers, Quatrefages describes uncini here also. In 
accordance with this, Quatrefages distinguishes three regions 
of the body in the Maldaniea, of which the middle one (regio 
intermedia) embraces the large and always preponderant num- 
ber of segments furnished with sete and complete rows of un- 
cinl. ‘The uncini, always of an elongated sigmoid form, are 
distinguished from all similar ones by the circumstance that 
beneath the apex of their usually multidentate beak a band- 
like chitinous lamina is placed. The cephalic and caudal ex- 
tremities are so arranged that, although they do not prevent 
ingress to the tube constructed by the animal, which is open 
at both ends, because this is much longer, they very conve- 
niently protect it im its tube against an intruder. ‘They are 
constructed on much the same plan as in the Pectinarie, the 
dorsal surface of the buccal segment usually forming a firmer 
plate inclined forwards, and the terminal segment a similar 
plate inclined backwards, or a funnel, which correspond with 
the tube in diameter ; in the Pectinarie, however, the terminal 
plate belongs to several of the last segments, which together 
constitute a valve which can be turned downwards. ‘The 
cephalic lobe itself is but little developed in the Maldaniea, 
and is probably to be sought only in the narrow longitudinal 
strip, projecting in front as a free lobule, which divides the 
vertical lamina of the buccal segment into two parts for a 
greater or less distance, and is marked off by a furrow on each 
side. In order to establish a genus of Maldaniea, therefore, 
both the ends of the body, of which the structure is so charac- 
teristic, must be preserved; and this, owing to the readiness 
with which these animals are torn, is frequently not attain- 
able. Thus we know only the anterior halves of Clymene 
torquata, Leidy, Letocephalus parvus, Quatref., and Clymene 
ebiensis, M.-Edw., and of the genera Rhodine, Malmgr., and 
Mandrocles, Iphianissa, Neco, and Militta, Kinb.; Clymene 
