602 CAMBEIAN BRACHIOPODA. 



Matthew [1895a, PI. Ill] has given diagrammatic illustrations and elaborate descriptions 

 of a number of "embryonic" characters of Botsfordia pulchra. Prof. W. A. Parks, of the 

 University of Toronto, sent me (in July, 1906) all the material in the Matthew collection 

 representing this genus and species, but I was unable to recognize the originals from which 

 Matthew's drawings were made. It does not seem probable that his figures 2a, 2b, and 2c 

 represent a young shell of this genus, as it is represented with a high false area similar 

 to that of some species of Acroihele; the same is true of figure 2g. Of the other figures, Ik, 

 2k, and 2i appear to be the posterior portions of adult shells from which the anterior portions 

 have been broken away. 



There are two slabs of rock in the Matthew collection upon which there are a number 

 of distorted and poorly preserved interiors of the valves, some of which may have been used 

 in constructing restorations of the interior characters. 



Matthew [1891, p. 148] regarded Botsfordia as a subgenus of Oholus, as he did not dis- 

 cover that the ventral valve was perforated with a pedicle opening and that the dorsal valve 

 was much like that of Acroihele. Redlich [1899, pp. 5-6] proposed the genus Mohergia for a 

 generically similar species, therefore his name becomes a synonym of Botsfordia. Redlich 

 [1899, p. 6] compares Mohergia with Oholella, an observation that was based on keen appre- 

 ciation of the cleft or pedicle groove and the arrangement of the muscle scars in the ventral 

 valve; the dorsal valve he compared with that of Acroihele. He said [1899, p. 6]: "The agree- 

 ment goes so far that we may consider Oholella crassa [Walcott, 1886b, p. 114] and Acroihele 

 granulaia [Linnarsson, 1876, p. 24] as the extreme forms of Mohergia." The difference between 

 the ventral valves of Oholella crassa (Hall) and Botsfordia is that in the latter the pedicle groove 

 ■ and area have disappeared and a narrow listrium takes the place of the area, the pedicle open- 

 ing passing through the shell, while in Oholella the pedicle opening is above a clearly defined 

 area. The dorsal valve of Botsfordia is more like that of Acroihele. The young shells of 

 Oholella may have been provided with a pedicle opening in the young stages of growth, much 

 like that in the adult stages of Botsfordia. Botsfordia appears to be a primitive form of Acro- 

 tretidse to the extent that the false area of the ventral valve is only a thin band between the 

 pedicle opening and the posterior margin, whereas in Acrotreta there is a well-developed false 

 area. Botsfordia appears to represent the first, or, at least, an early stage between the open 

 pedicle furrow of Oholus and the inclosed pedicle tube of Acroihele and Acrotreta. Botsfordia 

 differs from Acroihele by the form of its visceral area and position of the main vascular sinuses 

 in the ventral valve, also the position of the pedicle opening. 



The cancellated surface of Botsfordia pulchra (Matthew) is sinailar to that of Micromitra 

 {Iphidella) pannula (White) (compare PI. LXII, figs. 5, 5a-c, with PI. IV, figs. Is, It). The 

 forms of surface in B. granulaia (Redlich) and B. cxlata (Hall) are often found in species of 

 Oholus {Westonia) and Lingulella {Lingulepis) (Pis. XLIV, XLVII). The surface of Acroihele 

 (RedlicheTla) granulaia (Linnarsson) (PI. LVI) is similar to that of Botsfordia granulaia (Redlich) 

 (PL LVII). In Schizopholis rugosa Waagen the false cardinal area is more developed than in 

 Botsfordia, and the apex is elevated. Schizopholis appears to be a form intermediate between 

 Botsfordia and Acrotreta. At present the species of Botsfordia known to me are B. pulchra 

 (Matthew), B. cselaia (Hall), B. granulaia (Redlich), and B.? harrandei Walcott. 



Botsfordia? barrandei Walcott. 

 Plate LVII, figures 7, 7a-b. 



BracMopode nouv. gen. de Veenetjil and Barrande, 1860, Bull. Soc. g6ol. France for 1859-1860, 2d ser., vol. 17, 

 pp. 536-537, PI. Vin, figs. 5, 5a-e. (Described and discussed in French as a new species. Figs. 5, 5a-b are 

 copied in this monograph, PI. LVII, figs. 7, 7a-b, respectively.) 



Acrothele Pompeckj (in part), 1896, Jahrb. K.-k. geol. Reichsanstalt for 1895, Bd. 45, Hft. 8, p. 603. (Discussed in 

 German, changing generic reference; see p. 603 for translation.) 



Botsfordia ? harrandei Walcott, 1908, Smithsonian Misc. Coll., vol. 53, No. 3, pp. 77-78. (Discussion in the preced- 

 ing reference translated and species described and discussed as on p. 603 as a new species.) 



