AN ATTEMPT TO REVISE THE FAMILY (( LIXGUATULIDAE )) IJ.J 



P. annulatus I hâve given the characters of their autlior and added 

 those of Leuckart. I hâve also added a few détails which might assist 

 in the identification of those species such as P. teretiusculum, whose 

 anatomy has been more fully worked out, such détails being as a 

 rule conflned to the external features. My reasons for departing 

 from the strict rule of giving the diagnoses of the authoj- of the 

 species in the case of Diesing and some of the earlier writers and 

 giving that of Leuckart, are that the latter worked over the subject 

 in a much more complète and systematic manner than was possible 

 in 1836 and that he includes their diagnoses in his much fuller and 

 more complète account of each species though not always in the 

 same words. I hâve added diagnoses of such species as seem to 

 me to be valid, which hâve been described since 1860, the date of 

 Leuckart's Monograph. 



As a rule the adult Linguatulidae are found in the nasal cavities 

 and spaces communicating with them as well as in the lungs of the 

 Carnivora, Snakes, Crocodiles and flesh-eating animais generally. 

 The larval forms are usually found free in the body-cavity or encap- 

 suled in or on the walls of the alimentary canal, the liver, spleen, 

 mesentery or abdominal muscles, of smaller animais on which the 

 former prey. In fact they lie in some position not far removed from 

 the alimentary tract from whicli they hâve presumably migrated. 

 In some cases both adult and larval forms move about in the body 

 of their host. When the former are found in the mouth and throat, 

 they are probably making their way out of the body, this is 

 especially the case when the host is dead. The active migrations 

 of the larvae through the tissues may cause fatal results (1). 



In the lists of hosts, I hâve tried to give the British Muséum 

 Catalogues' names (in brackets) for the older species described by 

 Rudolphi, Diesing and others, but in some cases I hâve failed and 

 then the older name alone is mentioned. 



Family LINGUATULIDAE 



The family of the Linguatulidae may be characterised as foUows : 



Internai parasites with a vermiform body, ivhich is elongate, flatten- 



ed or cylindrical and usuaUif ringed, the rings varying in number. 



(l) See Cobbold's l'arasitea, London, 1879. 



