124 (i. F. MATTHEW: THE FAUNA OF THE ST. JOHN GROUr. 



EXPLANATION OF PLATE. 



Fig. l.—Paradoxidcs Acadicux, Fry, magnified 5 diam. 

 " 2. " " Pygidium of small individual of this species? Maguifled 2 diam. 



" 3. " lamellatus, Hartt, young, magnified, 2 diam. 



" 4. " " Side view of same head. 



" 5. " Pygidium of a larger species, to show scars, &c. 



" '• "'(XSTVa«/.„jHartt,sp., head-shield of adult, flattened. 

 " 7. " " Front view of same head. 



" 8. " " Genal spines of this species. 



" Glabella, &c., of young, magnified 3 diam. to show arrangement of the spines. 



" Cheek of adult enlarged 2 diam. to show ocular ridge and ramifications. 



" Thorax of half-grown animal, showing seven segments. 



" Thorax of rar. ;•. side view, showing fourteen segments. 



" Pygidium of adult, natural size, 



" " " magnified 2 diam. to show the markings of the surfaca 



,1 « ti il 11 11 11 " gi(je view. 



" " " tar., half-grown, -with curved base. 



" Embryonic stage (?) magnified 10 diam. 



" First stage, magnified 10 diam. 



" Third stage, magnified .5 diam. 



" Fourth stage, " 4 " 



Fifth stage, " 2J " 



" Size 9x17 mm. " li " 



N.B. — A specimen, having only the part of the head below the, dotted line 



a a, possesses genal spine and part of thorax. 



" Segments of this thorax enlarged to show spines on the edges of the plurœ. 



" Individual nearly full grown with pentagonal frontal lobe. 



i'>Çori/plii' ^ \ Hartt, sp., typical form shortened by pressure, with distinct furrows. 



(Bmliclla) Bauiyi, S > i > Jf . i > 



" Var. a., with smooth test. 



" Same variety in profile. 



" Pygidium. 



" A very young individual, magnified .5 diam. 



" Another small shield, magnified 4 diam. 



" Larger, " 1Î " 



elegans, Hartt, sp-, below the adult size. 



" Front view of a head of this sjjocies. 



" Pygidium. 



" A very young individual, magnified 5 diam. 



" A larger one, " 2^ " 



" A still larger shield, " IJ " 



" Far., flattened by pressure, shewing transverse ridges on the glabella. 



Baileyi ? Young, magnified 3 diam., shewing transverse ridges on the glabella. 



Walcotli, N. sp., somewhat distorted. 



'' Markings of inside or test, magnified. 



