.tt)H.—\.\' KLEtt. [sect .mur. axe FRAM
\lrnrlnre .~ untnrtumttely unavailalile‘l In this all subsequent investigator» uhn have dealt \\'lllt thi~‘ subject. are unanimous. l lttht} nnw ~nrt-eeded in uhtaining the prunt by reteret - tn the
Inici-tm-upir .‘lrurture The latter has luzen t'uund tn agree entirer on
lln- nne hand with the structure nt Hmmnmsll'ns, and on the other to r-«mnldu In a great extent that nt I’lm‘uspist [u the case of the latter the dilterent-e only t-nmisls in the rirrmnstam-e that the vaseular canal fixlt‘ln is vmnpnsed ut more regula ~ lacunes. and that the dentirles are welded together into lungiludinal rlhs.
This agreement with Plernapidue, which is thus apparent in the ~trnrtnre at the hotly plates, is even more evident when we consider the tnrln and arrangement of the hody plates.
We can hardly he in dnuht as to hnw the large hody plates may he identified in thew two types. That side at Drepanuspis which was ult-ntitied hy 't‘aaumm as the \‘eutral. in the median line has ‘2 large plates tnltuwing earh nther, tTmuuam's median ventral and mental platel. At the ~ides we see the long rnrnual plates. amt in trout nl the<e the 2 plt'l't'i‘d nrntar plates. These tllllte correspond tn the plates nn the dnreal side nt Pteruspis, with its median dorsal plate, rostrum. lu-n cornua and two ocular plates (la the other side, whirh is identified h_\' 'l'nanmm as the dm'sal. the large nval plate which 't‘naul‘ua described a~ lln' na-dian (lttl‘afll plate, agrees pertertly with the large ventral plate at [Yuma-111's. The mid plate agrees in the case of the twu families. llnl unly in it arrangement hut also in “5 form. The sole divergence u tnnnd in the ellttl'i tnrm of the, I‘Ustl‘fli plate. whirh however i~' quite natural in the light ut tln- ray
ke tmdy torm nl qunnmspist
ln runsequenre. it would he vxren-diugl)‘ remarkahle if the Sltlt-‘s at the hind)" \rhirh in the vase at these so eluser related \lbl't'lt'w ari- rharnrteriwd hy lllt‘ same develupinenl and arrangement nt plates. .~lluul|l not he identirali
itt mnrw :lll inveatigatnr like ’l'nAwUAm has nut nrerlnuked this .vn-u-nnhtanr hut nor
rtln-Iem' he nr \‘ed at the nppnsite rmu'lmiou. 'I'In- lllttxl lltllml‘ltttll reamns tnr thix :Il't' xunnned up hy him in his ~npph~nwnlnl nm-k‘ un Ilt‘l'llllltllsllih‘ 11> tulluw.'.
| Mihmit [lion-turn. that l have amply shown -—
’t‘hut tlw ahnr I tbln} I of the vurapuueot1)repunuspts
In vmnridvnt with the apparent dur~a| luhe" nr :hpt‘t’l nt thermnlal tin.
~t.,tl.I-m.vm In llu' anw llv'uminu l"l~ltt>~ “1'1: mimd page 47 .
