50 CONTRIBUTIONS TO q.ENEKAL UEOLOGV, 1913. 



Equisetum collieri n. sp. 



Plate V. (igure 5. 



Stem vorv little flattonod or distorted, about 6 or 7 millimotors in diameter and about 

 5.5 centimeters loufi between the nodes, slightly swollen in the nodal rejrion, and with about 

 eight relatively very strong longitudinal ribs and corresponding channels; sheath very short, 

 appressed; teeth aj)parently of the same number as the ridges, about 12 millimeters in length, 

 slender and sharply acuminate at apex, each hing closely appressed in a groove; tubercles, 

 or enlarged subterranean portions, present at the lower node. 



This species is based on the only example noted in the Collier collections and has been named 

 for the collector. As may be seen, it has been little flattened or otherwise distorted and may 

 be viewed nearly in its entirety. It is chiefly remarkable for the vexy prominent ribs and corre- 

 sponding channels, and the short sheath witli the long, slender acuminate teeth closely appressed 

 in the tlepressions. 



I have verv little doubt that this is the same as the form from Cape Boheman, Spitzbergen, 

 described by Heer ' under tlie name Equisetum i-uguJosum. though the present form is better 

 preserved and admits of a fuller description of the essential characters. The size and the jiromi- 

 nent ribs arc evidently similar in both, though the Spitzbergen specimen is not swollen in the 

 nodal region, and of course the character of the teeth can not be made out. Rather than make 

 a doubtful identification, however, I have placed the Alaska specimen under a different name. 



This species is also similar to the specimen of Equisetum burejense from Amurland shown 

 in one of the figures given by Heer.- This figure shows a porticm of a stem with parts of two 

 nodes and an attached "tuber," as well as several scars, whence apparently other "tubers" 

 have been broken. The figure of E. collieri shows the presence of a "tuber" of similar size and 

 ap])earance, at least so far as can be made out, at the lower node. The size of the stem is similar 

 in the two forms, though E. burejense is not swollen in the nodal region nor are the longitudiuiU 

 ridges so prominent. 



Seward,^ in commenting on Equisetum burejense, says: "These incomplete specimens may 

 be tubers of Eciuisetites, but they are hardly worthy of a specific name." This attitude of 

 mind in dealing with obscure oi biologically uncertain forms is not the right one, in my opinion, 

 for if a plant is sufficiently well characterized to be used as a stratigrajiliic mark its usefulness 

 is increased by giving it a definite name that can be employed for reference, whether it is bio- 

 logically allocated or not. 



.Vathorst,^ who reviewed Heer's Cape Boheman material, reduced not only his Equisetum 

 rugulosum but also E. bunburyanum Heer anil Phytothcca latiralis'. Heer to f^quisetites sp., 

 remarking that they are too poorly preserved and doubtful to be maintained. The fine trans- 

 verse lines on Equisetum rugulosum spoken of by Heer are, according to Xathorst, only checks 

 in the carbonaceous covering. Be this as it may, there does not appear to be any doubt as to 

 the correctness of referring the present Alaska form to Equisetum. 



OtozaiMites oiganteus Thomas. 



Plate VI, figure 2. 



OlozamiUs gifianteus Thoma.s, Jurassic llora of Kamenka: Com. p;6)l. M^ni., new ser.. pt. 71, p. ,H4, PI. VI. ligs. I, 2, 

 Hill. 



The single example figured is the only s])ecimen of this species that has been foimd. It 

 consists of a ])ortion of the rachis about 4 centimeters in lengtli and the basal portions of tliree 

 leaflets, only imc nf wliicli, liowever. is anywlicrc near perfect. This most j)erfect Icillct is I." 

 millimeters witic and is preserved for a length of about 4.5 centimeters and was presumably 



' TTecr, Oswald, Flora fos,silis arctica, vol. 4, pt. 1, p. 32, PI. VI, fig. 19, 1876. 



'- IdiTn, pt. 2, p. !i<", PI. -XXII, ng. .S, l,S76. 



' Seward, \. C, Juras.sU' plants from Amurland: Com. g&>l. M^m., new ser., pt. 81, p. 20, 1U12. 



< .Vatliorst, .\. 0.,Zur mewzoischen Flora Spitzbergens: Kongl. Svenska Vetenskaps-Akad. Ilandl., vol. :iO, p. I2, isii;. 



