258 REV. O. p. CAMBRIDGE ON NEW [Feb. 15, 



" The Tiaamous, largely specialized into a kind of low gallinaceous 

 carinate type, yet retain the same form of skull and face as the 

 Ratitse. Thinocorus also retains much that is dromueognathous in 

 its skull, mixed with normal schizognathism : but superadded to 

 these characters we find an intimate union of the broad vomer with 

 the largely developed alinasal floor ; a little more metamorphosis, and 

 the palate would have corresponded with that of the Passerine birds. 



"But in this bird, as in the Hemipod {Turnix) it is not in the 

 structure of the vomer and its relation to the nasal labyrinth that 

 we find all the Passerine characters. The face, generally, is rich in 

 such modifications : I showed them in my former Part with regard 

 to Turnix, and in this in the genus Thinocorus. 



" In the marvellously specialized skulls of the Passerinse unlooked- 

 for osseous centres often appear ; these are often very uniform in 

 certain families which are more or less allied. 



" The first I may mention here are the "palato-maxillaries ;" these 

 are a pair of bones, separately representing the ingrowth of our upper 

 jaw-bone which forms the "hard' palate." I find these in the 

 following families, namely Tanagridse, Brachypodidse, Mniotiltidae, 

 Ccerebidae, Cardinalidae, Icteridse, and Emberizidaj. In some 

 families, besides lesser ossicles added to the vomer, one on each 

 shoulder, the vomer is not merely composed of a right and left half, 

 but each moiety is more or less broken up into two centres, llere 

 we have repeated the tetramerous vomer (vomers and ' septo- 

 maxillaries') of the Snake and the Lizard. The families showing 

 this structure more or less clearly are the Mniotiltidae, Ccerebidae, 

 Vireonidse, Muscicapidse, and Saxicolidae. 



" With the exception of Menura, the South-American types are 

 most generalized, low, and, I may say, ancient ; next to them the 

 Australian birds, and those from Malaisia and Central America ; 

 whilst the most highly specialized types belong to the northern 

 hemisphere generally. 



" Looked at from my particular morphological stand-point, facts 

 like these seem tome to be well worth the pleasant labour 1 have' 

 spent in obtaining them." 



This paper will be published entire in the Society's * Transactions.' 



The following papers were read : — 



1. On a new Order and some new Genera of Arachnida from 

 Kergnelen's Land. By tlie Rev. O. P. (JambridgEj M.A., 

 C.M.Z.S., Hon. Memb. New-Zealand Institute. 



[Eeceived January 15, 1870.] 



(Plate XIX.) 



The few examples of Arachnida found during the late Transit-of- 

 Venus Expedition to Kergnelen's Land, and kindly sent to me by the 

 llev. A. E. Eaton, I propose now to describe and figure. Almost 



