1 "ll; l II. OB ( OROXK i l; \n BR \\< II. 185 



ami Baddies are, howev< l. not deeply divided by th< 



i tin- last named species The abdominal lobe i- one balf longer than 

 1 1 * • - superior laterals, ami tin- inferior lateral the superior lateral* 



in tin- same proportion. 



oe suite «»t' theae specimens exists in the Museum of Stuttgardt, sho 

 tie- variations described nbove. Some are verj decidedly planicostan in n 

 but nut more so than other specimens "i I '-. in which the keel be< 



ly suppressed, ami the nbdomi y the pilae. Young specimens 



from Behla pass tlirough stages which repeat exactly the charai 



when considerably older ami perhaps full grown. One of these i- labelled 

 hi variety; another lot of three specimens is named 

 /' ml ni their thick whorls ami pilse. A large specimen from 



Gmiind, on the hut part of the last whorl, ha- all the characteristics of the -tout 

 I :i- ofvar. G I; - There i- also a fragment of a much 



older -hell, the dorao-abdominal diameter of the whorl being 60 mm., which baa 

 similar characters The chann Is are. however, very broad ami -hallow, ami the 



• • the above ami the description of var. Qatidryi were written. 1 have 



found in th Election of the Museum of Comparative Zoology English 



- exhibiting the young. In these, for <>ne <>r two volutions, 



the whorls are smooth, then obscure tubercles or Bwellings begin to appear upon 



lea, which elongate into folds on tin- third whorl, ami I.e... me distinct pilaa 



on the latter put of this whorl or the lir-t quarter of the fourth. The external 



the young I J - omplete in the pilse, the com- 



I or embryonic form of the whorl, and the • i keel; th'' sutures, 



similar. Even on the early portion- of the third 



whorl tin- abdominal lobe i- quite long, the superior ami inferior lateral lobes 



lingly short and the corresiwnding saddles of equal depth. From this 



time thi- complication consists in the crenulation, or rather serration, of the mar- 



ind th'' -low increase of depth in the superior lateral Baddies . the other 



■addles and lobes remain about what tie \ were at first with regard to their 



Th" L. • ! is perceptible as a slightly raised siphonal line on th 



the fifth whorl or last of the fourth. In the first ■>! tin- stage, the 



abdomen, pilaa, ami form of the whorls are similar to those of the adult • 



On the fifth volution, however, the abdomen becomes flatter, th< 



nicular haul of the pike t •• abrupt, and finally tuberculated, ami th.' hitherto 



•live! M'1 Blightly convergent 



Tie ! b) Quenstedt ' are qui I 



pletely pilated than i- usual in t! • md the form of the whorl i- 



diffen at We doubt tie the identification. 



