4 6o SCIENCE PROGRESS 



(both in Ann. and Mag. Nat. Hist. September 191 5). F. W. 

 Edwards writes " On Elporia, a New Genus of Blepharocerid 

 Flies from South Africa " (Ann. and Mag. Nat. Hist. September 

 191 5). Prof. T. H. Morgan has already rendered the fly 

 Drosophila a classical form for zoologists, and is continuing 

 his studies thereon. He has recently dealt with " The Role 

 of Environment in the Realisation of Sex-linked Mendelian Char- 

 acters in Drosophila " (American Naturalist , July). He con- 

 cludes that the amount of water in the food determines the 

 realisation of abnormal types. However effected, it is possible 

 for the experimenter to determine at will the nature of the 

 flies by controlling the food supplies. The abdomen is some- 

 times abnormal, possibly as the result of injury, but the 

 evidence shows that such a condition in the parent has no 

 effect on the offspring. In the same fly Short — " A Note on 

 the Gonads of Gynandromorphs of Drosophila ampelophila " 

 — makes the interesting discovery that in lateral gynandro- 

 morphs the gonads do not follow the separation of the 

 somatic cells into male and female, but on the same side are 

 always either male or female. 



Vertebrata. — The " Origin of Bilaterality in Vertebrates " 

 has been investigated by Enclesheimer (American Naturalist, 

 August). The eggs of a number of Anurous and Urodele 

 Amphibia were employed, and it was found that the bilaterality 

 reveals itself through the early cleavage grooves. Several 

 theories of the homologies of the ear bones in higher vertebrates 

 have been put forward, and Goodrich has attacked the question 

 of " The Chorda Tympani and Middle Ear in Reptiles, Birds, 

 and Mammals " (Quart. Jour. Micro. Sci. vol. Ixi. pt. 2). He 

 finds it is remarkably uniform in its development, and is always 

 a postrematic branch of the facial nerve, save in the chick, 

 where it is pretrematic. The relations of the parts bear out the 

 view that the proximal region of the columella corresponds to 

 the stapes, the quadrate to the incus, and the articular to the 

 malleus. Collinge has a " Note on an Interesting Abnormality 

 in the Mandibular Arch of Chimcera monstrosa " (Ann. and 

 Mag. Nat. Hist. August). " Descriptions of Two New Lizards 

 from Australia" are furnished by Boulenger (Ann. and Mag. 

 Nat. Hist. July), and Schmidt has written " On a New Flat-fish 

 of the Genus Arnoglossus from the Black Sea." 



The mammals receive a fair amount of attention in the 



