09 
taxon of which is unknown. Until such time as we are able to base the 
subfamilial classification of such genera on explicit and well-sup- 
ported hypotheses of cladistic relationship, we prefer to regard their 
subfamilial affinities as uncertain. 
Genus KAWINA Barton, 1916 
Cydonocephalus Whittington, 1963: 97. 
TYPE SPECIES. Cheirurus vulcanus Billings, 1865, from the Cow 
Head Group (lower Whiterockian), western Newfoundland; by origi- 
nal designation. 
DISCUSSION. Whittington (1963: 97) distinguished his new 
Cydonocephalus (type species C. griphus Whittington, 1963, lower 
Whiterockian, western Newfoundland) from Kawina Barton, 1916, 
on the assertion that the ‘glabella is most convex anteriorly (not 
posteromedially) and juts forward, lobe 1p, and in some species 2p 
and 3p, are gently inflated, and occipital furrow curves forward (not 
back) medially.’ Of these features, only the glabellar convexity holds 
for all six of the western Newfoundland species assigned to 
Cydonocephalus. The glabellar lobes of large specimens of C. 
torulus Whittington, 1963, are not markedly more inflated than 
those of Kawina vulcanus (Billings, 1865) (compare Whittington 
1963: pl. 28, figs 5, 16), and the occipital furrows of both C. torulus 
and C. griphus both clearly curve backward (Whittington 1963: pl. 
27, figs 3, 10, 13, 16; pl. 28, figs 1, 5; pl. 29, figs 1, 4). 
All of the pygidia (Whittington 1963: pl. 31) which likely belong 
to species assigned by Whittington to Cydonocephalus have their 
pleural ribs fused along almost their entire length. Kawina arnoldi 
Whittington, 1963, however, has ribs with distally free tips 
(Whittington 1963: pl. 26, fig. 14). This is similar to the Irish species 
(Pl. 7, fig. 2), the pygidium of which differs from that of K. arnoldi 
only in proportions. However, the sagittal profile of the Irish cranidia 
is obviously like that of Cydonocephalus, with the point of max1- 
mum convexity anterior, not posterior. Kawina arnoldi, however, 
lacks the strong posterior convexity of the type species, and has a 
nearly evenly arcuate sagittal cranidial profile (Whittington 1963: 
pl. 26, fig. 8). 
Considering all the species it is not possible to specify 
synapomorphic characters that would distinguish the two genera as 
separate monophyletic groups. Rather, species presently assigned to 
one or the other show overlapping variation in characters considered 
by Whittington to be diagnostic of Cydonocephalus, as well as in 
pygidial morphology. For these reasons, Cydonocephalus is placed 
in subjective junior synonymy of Kawina herein. 
Kawina divergens (Reed, 1945) 
Pl. 6, figs 13-16; Pl. 7, figs 1-5, 7 
1909 Pliomera aff. fischeri (Eichwald); Reed in Gardiner & 
Reynolds: 144; pl. 6, fig. 4. 
1925 Kawina sp., Raymond: 144. 
1945 Kawina divergens Reed: 59. 
1971 Kawina? divergens Reed; Lane: 56; text-fig. 9a. 
1988 Kawina? divergens Reed; Morris: 119. 
DIAGNOSIS. Dorsal sculpture of very fine, densely spaced gran- 
ules; short, thorn-like genal spine retained in large holaspides; 
glabella with nearly even sagittal convexity, point of maximum 
convexity anterior; pygidium wide, with splayed, subquadrate ribs 
bearing free tips. 
J.M. ADRAIN AND R.A. FORTEY 
HOLOTYPE. Pygidium, SM A10396 (PI. 7, fig. 2); topotypes It. 
26015-26022, 26200. 
DESCRIPTION. Cranidium with sagittal length 70-75% of maxi- 
mum width across posterior border; glabella with width across 
midlength (exsag.) of L2 subequal to or slightly narrower than width 
across midlength of L1; maximum glabellar width subequal to 
length (measured in sagittal profile) excluding LO; anterior border 
short but complete medially; preglabellar furrow deeply incised, 
grading abaxially into axial furrow of similar depth; anterior fixigena — 
a narrow, laterally convex strip, widest opposite midlength (exsag.) 
of L3, narrowing posteriorly in front of palpebral lobe; palpebral 
lobe narrow, entirely set off from interocular fixigena by very 
sharply incised palpebral furrow; interocular fixigena broadening 
posteriorly, smooth, with moderate dorsal convexity; interocular 
fixigena grading smoothly into broad posterior fixigena, held in 
plane declined about 60 degrees from horizontal; anterior sections of 
facial sutures short (exsag.), parentheses-shaped, with strong ante- 
rior convergence from midlength of L3 to front of glabella; glabella 
strongly inflated, sagittal profile with nearly even dorsal convexity, 
slightly more pronounced anteriorly; S1 nearly transverse distally, 
curved in nearly subcircular arc proximally, similar in depth to axial 
furrow but shallowing abruptly in front of SO so that L1 is not quite 
fully isolated; L1 with only slight independent inflation, length 
(exsag.) subequal to width (tr.); S2 similar distally to S1, proximal 
part shorter and less posteriorly inclined; L2 with no independent 
inflation, length (exsag.) 80-85% of that of L1; S3 as deeply incised 
as S| and S2, but not reaching as far adaxially, with less posterior 
curvature, and shallowed slightly near contact with axial furrow; L3 
with slight anterolateral inflation, length about 80% of that of L2; 
frontal glabellar lobe with slight lateral inflation immediately ante- 
rior to S3, anterior margin with blunt anterior convexity; SO composed 
of three distinct posteriorly bowed regions, two lateral ones behind 
LI, and a medial one between the L1 lobes, depth similar to axial 
furrow, medial region slightly longer (sag., exsag.) than lateral parts 
(exsag.); LO similar in length to distal parts of posterior border, with 
nearly flat top in sagittal profile; posterior border sharply incised, 
very short (exsag.), and running nearly transversely to genal angle, 
where it is bowed anteriorly; posterior border very short proximally, 
but lengthening greatly distal to fulcrum to form lobate genal angle; 
short, thornlike, subtriangular genal spine retained on even largest 
specimens; entire dorsal cranidial surface with very fine, unimodal 
granular sculpture. 
Librigena poorly known; field and lateral border both with fine 
granular sculpture similar to that of cranidium; lateral border well 
defined posteriorly, but grading into field anteriorly; lateral border 
furrow with concomitant shallowing anteriorly; field apparently 
quite narrow (tr.); eye unknown. 
Rostral plate unknown. Hypostome with sagittal length 75% of 
maximum width across anterior wings; width across shoulders 80% 
of width across anterior wings; width across posterolateral corners 
two thirds that across anterior wings; anterior margin (hypostomal 
suture) with strong anterior convexity; sharp marginal rim and 
furrow developed laterally, middle body extended to margin medi- 
ally; strong antennular notch between shoulder and anterior wing; 
lateral border broad and inflated, with fine granular sculpture; lateral 
border furrow shallow and broad (tr.); posterior margin with only 
slight posterior convexity; posterior border and posterior border 
furrow similar in dimensions to lateral border and furrow; middle 
body with sagittal length slightly greater than maximum width, 
moderate ventral inflation, strongest anteriorly; sculpture of fine 
granules somewhat more subdued than that of lateral border; middle 
furrow impressed only laterally, strongly declined posteriorly. 
