86 I, Sie, (G OIILIE, SZ 
ance to the lateral appendages found in Caryocaris, but to them only. Had 
these structures stood alone without evidence of further organization, I should 
probably have referred them to Dawsonza. But although a majority of these 
appendages are found isolated, in C. od/omgus all of the few specimens- 
obtained, and in the other two species, a not inconsiderable number of speci- 
mens are found paired in such a way as to leave no doubt that this is their 
normal condition, and their separation a result of decomposition. Further in 
several (of course very exceptional, but evidently so only as being exceptionally 
favorable preservation-conditions) specimens of C. wrighizz | have seen these 
symmetrically paired lateral appendages attached to the distal end of a single 
median proximal portion on which I believed thecz could perhaps be traced. 
It seems very doubtful indeed whether the future will show similar organiza- 
tion in any species at present referred to Dawsonia. 
It is needless to add (as Professor Lapworth points out) that this is not, as 
Salter supposed, a Crustacean, but from its resemblance to Dawsonza appears 
to be a graptolite. 
Caryocaris wrightit Salter, 1863. Plate V., Figs. 1, 2. 
Quart. Jour. Geol. Soc., London, XIX., p. 139, Fig. 15. 
Polypary, consisting of a proximal portion, two lateral and one (two?) 
median appendages. Proximal portion acutely triangular, 9™™ long, 3™™ 
wide ad max. (at insertion of lateral appendages). Condition of thece 
uncertain. Lateral appendages round-triangular, obliquely truncated superi- 
orly by the superior margin, 7™™ long, 2.5 to 3™" wide ad max. (at point of 
divergence of adjacent margins), apex proximally directed, appareutly 
inserted upon the proximal portion through the medium of the “tubercle” 
which lies just within the outer margin; outer margin almost straight, bor- 
dered by a single filament which is interrupted by openings which appear to 
be continued into the substance of the appendage; superior margin slightly 
convex, running downward and inward, finally overlapping (or underlapping) 
the corresponding margin of the opposite appendage, furnished with a row of 
cilia-like processes ; inferior margins curving downward and outward around 
the “tubercle” to join the outer margin at the proximal extremity. Median 
appendage somewhat shorter than lateral, the superposed adjacent margins 
of which it overlies) acutely isosceles-triangular, symmetrical with reference 
to median line of polypary, the equal sides almost straight, the apex project- 
ing in the notch left by the diverging superior margins of the lateral append- 
ages. 
Horizon and locality. 
Upper Calciferous, Summit, Nevada. 
The specimens occur only as flattened films, a condition unfavorable for 
the determination of structure. The symmetrical disposition of the lateral 
appendages would seem to imply a similar symmetrical structure in the 
