452 SUMMARY OF CURRENT KESEARCHES RELATING TO 



very doubtful. He has studied the hyobranchial skeleton and larynx of 

 the new form, and finds that, though the former presents some unique 

 peculiarities, it also possesses those which characterise Pipa and Xenopus 

 as contrasted with all Phaneroglossal Anura. The larynx of both sexes 

 is of simpler structure than that of the two sexes of Pipa and Xenovus, 

 but presents resemblances to those of both genera. On the whole the 

 structure of hyobranchial skeleton and larynx in Hymen ochirus tends to 

 confirm the view that the Aglossa constitute a natural group, and that 

 the three genera now composing it have bad a common ancestry. 



In a note the author mentions the interesting fact that the carpus in 

 the new genus has the same structure as in Pipa ; that is, a single bone 

 only intervenes between the ulna and the fifth metacarpal, instead of two 

 as in Xenopus and all other anurous Amphibia. 



Nasal Secretory Sacs in Teleostei.*— Mr. H. M. Kyle has found in 

 Cynorjlossus semilaevis that the nasal organs which are placed symmetri- 

 cally on each side of the head communicate with a single large sac 

 occupying an area over the median portion of the roof of the mouth. In 

 one specimen examined, and termed by him " divergent," which may be 

 the type of a separate species or even genus, the roof of the mouth is 

 perforated by a large oval opening passing into a chamber corresponding 

 in position to the median sac in the ordinary forms, from which two 

 tolerably large canals pass to the nasal cavities, forming an effective 

 means of communication between the exterior and the mouth. 



The presence of nasal " sacs " is an adaptation to semi -sedentary as 

 opposed to migratory habits of life. In Labras, Scorpsena, Gastrosten*, 

 and Anarrhichas, forms leading a tolerably quiet life, simple water-re- 

 taining " reservoirs " are present. These are absent in the Gadidse, as 

 far as examined, and also in the herring — free-swimming migratory 

 forms. In the halibut, plaice, and turbot, which are ground feeders, 

 searching for their food almrst entirely by the sense of smell, definite 

 secretory sacs are present. 



In the Sole group, the tactile senpe, as shown by the development 

 of papillas and filamentous outgrowths of the integument, aids and 

 replaces the olfactory organ to a ceitain extent, and here the secretory 

 has given place to the water-retaining function. 



In the normal Cynoglosms the sacs, and in the " divergent" specimen 

 the nasal cavity, have the water- retaining function, and are not secre- 

 tory. 



The homology of the naso-pharyngeal communication in Cynoglossvs 

 with the internal nares in other Vertebrates, and with the condition in 

 Cyclostomes, is discussed. 



Air-bladder in Notopterus borneensis.j — Prof. T. W. Bridge figures 

 and describes the air-bladder of this species, with special reference to its 

 connection with the anditoiy organ. He finds that there is no direct 

 contact between the walls of the auditory caeca and those of the utriculi, 

 the two being separated by the membrane of the auditory fontanelles ; 

 nor is there any open tubular communication between the utricular and 

 the saccular portions of the auditory organs of the opposite sides of the 



* Journ. Linn. Soc, xxvi\ (1900) pp. 541-56 (1 pi.), 

 t Tom. cit., pp. 503-40 (2 pis. and 1 fig.). 



