oKDKll II 



AM.MONOIDKA 



r>:>5 



FIG. 113S). 



(Fig. 1188), which is highly involute ami nnnpresM-d, with Mat and narrow venter. 

 Sutures with nn>re or !.-> a.-ule ]uhe.~ and -addle-, as well a- a number \' ad\ i-nt itious 

 and auxiliary iullert i'>n>. Ventral lobe divided, and fannefo monoeboanitia Aperture 

 with hyponomic >inus, and tin- lateral 

 outlines simpler than in tin- next family. 

 Devonian. 



Family 3. Sageceratidae. Similar 

 to the last, but lateral lnl>e> bilid, ami 

 saddles acutely spade - shaped. Anti- 

 siphonal lobe bifid. Aperture has sinuous 

 lateral outlines with nv-ts at the ventm- 

 lateral ridges. 



Pseudosageceras, Diener ; ,sW</< ,-,/,/>, 

 }l'>js. (Fig. 1139). Permian and Trias. 



Family 4. Hedenstroemitidae. 

 Principal lobes and saddles with < eratitic 

 outlines as in Diseocampylij but adven- 

 titious lobes and saddles have Say en- m*- 

 like outlines. Antisiphonal lobe bifid and 

 very long. Dorsal inflections more com- 

 plex than in preceding families. Aper- 

 ture with ventral cre>t-. 



Hedenstroemia, Waagen ; Anaheden- 



m , /TT j \ $<n/i-i-ci'(i.< U" liUinji'i-i, Hauer sp. Upper Trias ; Mall- 



stroemia, gen. iiov. Type A. (Heden.) s t a dt, Austria. 

 Mojsisovicsi, Diener sp. Trias. 



Sub-Order F. DISCOCAMPYLI. Hyatt. 



Primitive genera show dose approximation to primitive types of Prolccanitidae. 

 Bases of saddles retain the entire rounded outlines of Lecanites even in *i<-!,iUsed genera, 

 but tJie lobes become completely divided by fine marginal serrations or digUations. Tlii.< 

 jut fly ceratitic outline is maintained more or less in all groups except ln'iililii *p /itlised 

 genera, in which the saddles are completely divided and the ctiacoeampytoc //. .> <li*ijipear. 

 lobe entire in primitive, bat bifid or trifid in specialised formi^ n<l :.itgous 

 imx ">>" mi tin <-,/ it ;tic outline in torn* genera. I'-nfnil l<>l>i* ///// broad 

 and short, <tn</ Inn-, >< ,-ij br<>ml .<i phonal saddles in titjiim! form*. 



The number of external inflections rarely exceeds three saddles and three lobes ill 

 primitive forms, and the first pair of lobes as a rule is very much longer and broader 

 than the others. While the eternal .-addle- ..fh-ii aasume aj^iroximately nu.noi-hyllic 

 outlines, the dorsal saddles commonly retain the, broader and less ditl'erentiated aspect 

 of Lecanitidae, and saddles never become divided. The number of dorsal inflections is 

 more limited inmost form< than in /'//<///m //?//,///, ami when lengthened l>y additional 

 inflections, the digitations are apt to be irregulai-. 



I. LECANITIDA. 



Compressed disco ida I mul inrolute forms. Compressed primitifa genera !<,, entire 

 sutures with broad run mini ,^////,x mid rather narrow lobes, the ventral lobe being broad 

 a ml shallow, and the sipli'ml .-</,/,//, also broad. Involute xln-lla ////W/// have pro- 

 longed lateral suture-lines with mi imlifmiti- number of often irregularly proportioned 

 inflections, which are really -marti/nul* iiriximj from the division of a prolonged -inn it- 

 saddle or near I it *tr!'_ilit, ill-pressed lobe-like, inm r lim: Dorsal sutures have similar 

 characters and the unf/ij>1ti>iinl ll>-, n-l/idi /V //*///' mn> i><>ii>tn1 in ^ri mitive forms, 

 usually remains entire on the sides and bifid at the esfri ui''fi<.< in sy/rc/,/ //><// /')////.-. 



