RECENT ADVANCES IN SCIENCE 41 



{Biol. Bull., vol. xxxvii, Oct. 1919) ; Shinji, " Embryology of Coccids, with 

 Especial Reference to the Formation of the Ovary, Origin and Differentiation 

 of the Germ Cells, Germ Layers, Rudiments of the Midgut, and the Intra- 

 cellular Symbiotic Organisms " (Journ. Morph., vol. xxxiii, Dec. 1919) ; 

 Strong, " Roughoid, a Mutant Located to the Left of Sepia, in the Third 

 Chromosome of Drosophila melanogaster " [Biol. Bull., vol. xxxvii, Dec. 1919) ; 

 and Riley, " Some Habitat Responses of the Large Water Strider, Gerri's 

 remigis, Say " {Amer. Nat., vol. liii, Dec. 1919). 



Vertebrata. — Tales of the wonderful power of Echeneis, or 

 Remora, the sucking-fish, have crept into zoological hterature 

 from the earliest times, and in " On the Use of the Sucking-fish 

 for Catching Fish and Turtles : Studies in Echeneis, or Remora, 

 III " {Amer. Nat., vol. liii, Dec. 1919), Gudger brings to a con- 

 clusion a series of inquiries on this subject. The previous parts 

 of this work dealt critically with all the known references to 

 the subject in reputable writings, and the sub-title, " Are these 

 Accounts Credible? " gives a fair indication of the scope of 

 the present instalment. The matter is gone into from the 

 point of view of the actual performances of the fish, and the 

 author's final summary is, " To the present writer, all the 

 evidence at hand sustains and confirms the stories of the living 

 fish-hook from the time of Columbus to the present day " ; and 

 it is good to find one fable of youthful days has some scientific 

 backing. 



Other papers include : 



Hubbs, " A Comparative Study of the Bones forming the Opercular Series 

 of Fishes " {Journ. Morph., vol. xxxiii, Dec. 1919) ; Bellamy, " Differential 

 Susceptibility as a Basis for Modification and Control of Development in the 

 Frog " {Biol. Bull., vol. xxxvii, Nov. 1919) ; Lillie, " The Early Histogenesis 

 of the Blood in Bufo halophilus, Baird and Girard " {Am. Journ. Anat., vol. 

 xxvi, Nov. 1919) ; Smith, " The Individuality of the Germ-nuclei during 

 the Cleavage of the Egg of Cryptohranchns allegheniensis " {Biol. Bull., 

 vol. xxxvii, Oct. 1919) ; Parmenter, " Chromosome Number and Pairs in 

 the Somatic Mitoses of Amblystoma tigrinum " {Journ. Morph., vol. xxxiii, 

 Dec. 1919) ; Rogers, " Experimental Studies on the Brain Stem : III, The 

 Efiects on Reflex Activities of Wide Variations in Body Temperature caused 

 by Lesions of the Thalamus " {Journ. Comp. Neur., vol. xxxi, Oct. 1919) ; 

 Pohlman, " Concerning the Causal Factor in the Hatching of the Chick, with 

 Particular Reference to the Musculus Complexus " {Anat. Rec, vol. xvii, 

 Oct. 1919) ; Hoshino, " A Study of Brains and Spinal Cords in a Family of 

 Ataxic Pigeons " {Journ. Comp. Neur., vol. xxxi, Dec. 1919) ; and Goodrich, 

 " Note on the Reptilian Heart " {Journ. Anat., vol. liii, July 1919). 



In " The Morphology of the Pulmonary Artery of the 

 Mammalia " {Anat. Rec, vol. xvii, Dec. 1919) Huntington has 

 thrown new light on this subject. In studying the development 

 of the pulmonary artery in the cat, he has shown that it does 

 not arise as an outgrowth from the ventral region of the sixth 

 or pulmonary arch, as is usually stated in textbooks. On the 

 other hand, it takes origin from a plexus of vessels derived 

 from post-branchial derivatives of the dorsal aorta in the lung 



