596 
F. H. EDGEWORTH. 
evidence of fusion, lay ventro-inedian and close to the ala 
temporalis, and was apparently homologous with the ordinary 
Mammalian pterygoid. 
The attachment of the (original) proxirnaP end of the 
tensor veli palatini to the pterygoid bone and hamulus is 
preserved in Man, Primates, Pinnipedia, Insectivora, Perisso- 
dactyla, Artiodactyla, Marsupials ; or it may altogether fail 
as in Cheiroptera, Carnivora, and Rodents (Kostanecki). 
The embryologhcal phenomena in the rabbit and pig show that 
the latter occurrence may, at any rate in some cases, be due 
to its non-development. 
The distal end of the tensor veli palatini in the rabbit 
becomes attached to the tympanic bone, whereas in Dasyurus, 
Didelphys and pig this ancient attachment is never gained. 
In the rabbit it persists up to the stage of 33 mm. (the oldest 
investigated), but judging from the account given by 
Kostanecki it is not present in any adult Mammal. It has 
yet to be determined in what orders other than Rodents a 
temporary attachment to the tympanic bone is gained. A 
secpndary attachment to other adjacent bones is gained in 
some orders, e. g. to the bulla ossea in Marsupials and 
Rodents. 
One almost constant feature of the distal end of the tensor 
veli palatini is attachment to the tensor tympani. Thus 
Kostanecki states that Der Znsammenhang zwischen dem 
Tensor veli und Tensor tympani ist bei vielen Saugethieren 
erhalten, wo aber ein soldier verloren gegangen ist, weisen 
doch manche Punkte auf die friiher bestehenden Beziehungen 
hill, die so sogar nur ini Anschluss daran erklaren lassen.^’ 
The developmental phenomena in Dasyurus, pig and rabbit, 
show that this connection with the tensor tympani is 
intimately related to the atrophy or want of development of 
the proximal portion of the latter muscle. 
1 The nomenclature adopted here is in reference to the original form 
and attachments of the pterygo-tympanicus, from which the tensor 
veli palatini is derived, and is the reverse of that used by Kostanecki. 
The tensor veli palatini is an interesting instance of transference of 
“ origin ” from the proximal end to the distal end of a muscle. 
