152 



in about 10 adult specimens the rostrum was qnite straight along 

 its whole length, running horizontally forwards, but in very young 

 individuals this is more often the case. 



Of 378 specimens the rostral formulae were the following : 



12 ^ . 9 + 1 . . 8 + 1 ^ . 



— two specimens, — ^ — six specimens, — - — twenty ninespecim., 



4 o 



12 . 9+2 . 8 



— one specimen, ^ — one specimen, — - two specimens, 



11 + 1 . 9 . . 8 „ 



— ^ — one specimen, — nine specimens, -— tour specimens, 



(4 o 



11 + 1 . 9 . 7 + 2 . ,^ . 



— ^ — one specim., - seven specimens, — ^ — eighty sixspecim., 



11 , . 8 +3 ^ . 7 +2^^. ^ 



- two specimens, - — two specimens, — - — thirty seven specim., 



•j o o 



10 . 8+2 ^ . 7 + l„ , . , , 



— one specimen, — - — two specimens, — — lortyeight specim., 



10 . 8 +2 ^ , „ . 7 + 1 , . 



— - one specimen, - — twenty five specim., -^ — twenty six specim., 



4 4 O 



10 . 8+1 . 7 + 



— one specimen, -— one specimen, — - — one specimen, 



9 + 1 . 8 + 2 ,, . 6 + 2 ^, 



— ^ — one specimen, - — three specimens, ~~. — tiiree specimens, 



9 + 1 . 8 + 1 ^ ^ . 6 4-2^ 



— _ — one specim., — - — seventy two specim., - — two specimens. 



5 4 ó 



These numbers demonstrate in the first place the yreat d'wersity 



7-f 2 



of the toothing formulae and furthermore that the formulae 



4 



ü_l_i 7+.1 7J_9 8-1-1 



in 86 specimens, -—— iu 72, ~\ in 48, — ~^ in 37, ^f^- 



4 4 c5 o 



7 -[- 1 

 in 29 and — - — in 26 specimens are those which iu most cases 



o 



are observed. In 198 of the 378 specimens seven teeth ') were 

 placed on the upper margin of the rostrum, i. e. in about 52 

 per cent., in 140 eiglit, i. e, in 37 per cent. of the total number 

 of specimens ; in 25 specimens, i. e. in 6,6 per cent., nine teeth 



1) Not coanting the apical tooth or teeth. 



