BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 
Comparative Measurements of Dinichthys Species. 
. H 
& ag En: E as 
; = 1 o 
= a ia a > > 2 gy 
q A =, A 4 Š ES 
N= ie Bad S bro di ae HS 
No. Species, ae” Ha IHs aa eo po Ey | ae 
© pA E A a ct E | > om 
En Br =] D D g BS 
E 8 | 8° El bp wl 88 
D A a3 F & El a | ME 
3 A pe 2 
3 E o ri 5 
1" Dsingehösaruid a A el a 76+ 
9 | ferteert. « . | 690°) 67.5 |, . | 68.0 
3 |“ terreli . . . | 56.25 | 65.0 | 86.0 57.5 
A sli che) epee . , . | 86.88 | 48.26 | 83.02 | 48.18 | 40.91 | 40.64 69.85 | 1.45 
alt et el le | er Ob. BOT POULT 1.87 
6 | © newberryi . . | 28.38 
7. Portege plastron |... sur.) ne un at 20.0 117.0 | 80+ 
Sal Degen en ei ee 12.6 |. 8+- 
9 |« intermedius . | 22.86 | 41.91 | 29.21 26.67 | 17.15 | 22.86 | 35.56 | 0.85 
AO mmor e a TIOE 1 20,0% 122 dao pr | ar: 1.59 
11 | Detached DM of 
Genesee Shale |. . . |. + 1126 | 18.75 
for. At the same time it must be remembered that the front margin 
of the plastron in all species of Dinichthys conforms to a peculiar and 
well marked type. 
To the right of the left antero-ventro-lateral is a small cleaver-shaped 
plate (7.5 cm. long by 3 cm. wide), the like of which is unknown among 
the derm plates of Coccosteids. It certainly does not belong to the 
dental apparatus, and is excluded from the orbital region on account of 
its size, There can be no doubt that the plate is entire, or nearly 80; 
but we must confess ignorance as to its position on the body. Just 
behind the unidentified plate is to be scen a small portion of the verte- 
bral axis, very imperfectly preserved, together with supports for the 
dorsal fin. The form of the neural arches is shown with some distinct- 
ness, as well as their articulation with the proximal row of basal carti- 
lages. The outer tips of the distal row of basals appear to have been 
bluntly terminated, or even swollen. 
