954 



TELEOPTILE— TENUIROSTRES 



and in fact ArcJiseopteryx (FossiL Birds, p. 278) and the Cretaceous 

 forms of North America (Odontoknithes, p. 649) had teeth. It is 

 highly probable that Teeth were a more or less universal feature in 

 all Birds of that period, that their loss took place at or shortly 

 before the beginning of the Tertiary period, and moreover that 

 their suppression was caused by the gradually increasing strength 

 of the horny sheath of the jaws, as in Tortoises and in young 

 Monotremes ; but it is not permissible to divide the Class Aves into 

 Birds Avith Teeth (Odontornithes) and Birds without. In Hesperornis 

 regalis there are 33 Teeth (p. 650) in each mandible and 14 in each 

 maxilla, Avhile the praemaxilla is toothless and was probably 

 covered with horn. All the Teeth stand in a groove (whence Prof. 

 Marsh's name Odontolcse), but bony processes between them indicate 

 a future alveolar condition. Each Tooth is curved backward, con- 

 tains a pulp-cavity, and consists of dentine •with an enamel coating 

 just as in the case of the normal Eeptilian Tooth, and another truly 

 Reptilian character is shewn by the succession of the Teeth, younger 

 and still imperfect Teeth being found on the inner side of the base 

 of the old or functional set. The Teeth of Ichthyornis are likewise 

 restricted to the mandibles and maxillse ; but they stand each in a 

 separate socket or alveolus (whence the name Odontotormse is applied 

 to this group of Birds), and the young or reserve Teeth are con- 

 tained in the pulp cavity of the older set, growing from the same 

 base just as in Crocodiles and in Mammals. The much more ancient 

 and still more Reptilian Archmopteryx had few Teeth, and those but 

 small. 



TELEOPTILE, see Feathers (p. 243). 



TELLTALE, the name long used in North America for Tofanvs 

 melanoleucus and T. flavipes (Sandpiper, p. 810) from "their faith- 

 ful vigilance in alarming the Ducks with their loud and shrill 

 whistle on the first glimpse of the gunner's approach," and accord- 

 ingly detested by him (Wilson, Am. Orn. vii. p. 57).^ 



TENDON, see under Muscular System (ef. 602-620). 



TENUIROSTRES, a French word used by Cuvier in 1805 

 (Leg. d'Aimt. Comp. tabl. 2) for a' group of Fasseres, containing the 

 genera Sitta, Certhia, Trochilus, Upupa, Merops, Alcedo, and Todus;^ 

 but its Latin appKcation seems due to Illiger in 1811, who restricted 

 it to the genera Nedarinia (Sun-bird), Tkhodroma and UpiqM 



^ For the same reason the Redshank, T. calidris, is known as Tolk (inter- 

 preter) in Danish and Swedish (c/. Tuknstone). 



- In the following year Dumeril {Zool. Analyt. pp. 46, 47, 64, 65, used the 

 word (also as French) in a double sense — fh'st almost precisely as Cuvier had 

 done, but next for a group composed of Recurvirostra, Tringa, Charadrius, 

 Numenius and Seolopax. 



