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Show 1894.] ANATOMY OF ATHERURA AFRICANA. 681 in this respect it differs from Hystrix and agrees with the Tree- Porcupines. 7. The brachialis anticus consists of two parts as in Hystrix, but these two parts are closely blended. In Sphingurus only the external or long head is present. 8. The extensor secundi internodii pollicis is absent in Atherura as it is in the Tree-Porcupines. It was found in Hystrix. 9. The pyriformis is present, as in the Tree-Porcupines. It is absent in Hystrix. I a m not inclined to place any great reliance on the presence or absence of this muscle, as it seems occasionally to miss its attachments to the sacrum and to rise from the upper margin of the great sciatic notch ; in these cases it becomes so closely connected with the gluteals as to be almost indistinguishable. 10. The biceps femoris consists of two parts, as in the Tree- Porcupines. 11. The peroneus quarti digiti is present as in Hystrix. In the Tree-Porcupines it is wanting. It will thus be seen that in most of these points Atherura agrees in its musculature with Hystrix, although in a few it approaches that of the Tree-Porcupines. Further observation is, however, necessary in order to eliminate individual variation, and to determine Avhich muscles are really valuable for classificatory purposes. The rest of the muscles were examined, but Avere found to correspond so closely with those of Hystrix that it would be almost a recapitulation of that animal to describe them in detail. THE DIGESTIVE SYSTEM. The tongue is long and narrow, and is marked by a median furrow Avhich is most distinct in the anterior part. The anterior third of the dorsum is covered by transverse rows of horny scales, the free edges of which are directed backwards and are serrated, but not so deeply as in Hystrix. There are usually three scales in each row. The posterior two-thirds of the dorsum of the tongue is covered with fine, backwardly directed, filiform papillae, which give the organ a velvety appearance. The fungiform papillae occur on each side of the median furroAv, but are most numerous in the anterior and posterior thirds of the organ. There are two circum-vallate papillae. The papillae foliatae consist of about ten parallel vertical slits, their posterior margin extending as far back as the level of the circumvallate papillae. O n the under surface of the tongue the fungiform papillae are seen to extend over the tip and, with some of the filiform, to cover about a quarter of an inch of the lower surface. The rest of this surface is quite smooth. , O n comparing the tongue of Atherura Avith that of Hystrix |