On Graptolites from Bolivia, collected by Dr. J. W. Evans in 1901–1902

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Abstract
The graptolites collected by Dr. John W. Evans from Bolivia, and sent to me for inspection, are marked as coming from five separate localities. The best-preserved forms occur in black pyritic shales exposed at ‘a halting-place on the right bank of the Rio Coranhuata, known as Culi, on the up-stream side of the Puente de Culi (J. 28/4/02).’ The rock is cleaved, and the graptolites are in consequence somewhat distorted, but the well-known species Didymograptus bifidus , Hall, is recognizable. Associated with this abundant form there is one small fragment of a slender extensiform Didymograptus , apparently of the type of D. affinis , Nich., but too fragmentary to admit of specific identification. Black shales occurring at another locality ‘on the left bank of the Rio Coranhuata, on the down-stream side of the Puente de Culi (H. 28/4/02),’ are crowded with graptolites, but unfortunately much distorted and in a poor state of preservation. On one slab from this spot several examples of a species of Phyllograptus are recognizable, and one of Glossograptus . The commonest graptolitic form present, however, is one which it is difficult to assign to any known genus or species. It belongs to the family of the Diplograptidæ, and possesses three conspicuous spines at its proximal extremity together with a long virgula distally produced. It is, perhaps, most closely allied to the genus Cryptograptus ; but all details as to the form of the thecæ are obscure, and the specimens are too distorted to allow of description. Another slab from the same

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