RECENT ADVANCES IN SCIENCE 235 



man, " Double Ureters in Human and Pig Embryos " (Ana/. Rec, vol. xv, Feb. 

 1919) ; Scammon, " On the Development and Finer Structure of the Corpus 

 Adiposum Buccae" (ibid., Jan. 1919); Senior, "On the Development of the Arteries 

 of the Human Lower Extremity" (Amer. Journ. Anat., vol. xxv, Jan. 1919) ; 

 Streeter, "Factors Involved in the Formation of the Filum Terminate " (ibid., Jan. 

 1919) ; and Thuringer, " The Anatomy of a Dicephalic Pig (Monosomus dipro- 

 sopus) " (Anat. Rec, vol. xv, Feb. 1919). 



General. — Jacobs, in " Acclimatisation as a Factor affect- 

 ing the Upper Thermal Death Points of Organisms " {Journ. 

 Exp. Zool., vol. xxvii, Jan. 1919), has made a study of the time- 

 temperature relation in bringing about the death of starfish 

 larvae and Paramoecium. The effect of a gradual rise of 

 temperature is different in the two cases. In the starfish 

 larvae, submitted to a gradual rise of temperature, death occurs 

 at the point where the summation of time-temperature factors 

 for the temperatures passed, reaches the total that is fatal to 

 the animal if it were submitted to a constant temperature for 

 a sufficient length of time to bring the total to the same amount ; 

 in Paramoecium, on the other hand, it is found that, if the tem- 

 perature be raised quite slowly, it is not killed until the summa- 

 tion of the t-t factors has exceeded the total of a constant 

 temperature-time total. This extra amount of resistance is 

 described by the author as "surplus resistance," and is inter- 

 preted by him as acclimatisation. Using the method of mea- 

 suring adopted in the paper, the starfish larvae are in the 

 vicinity of zero, while the Paramoecium was about 45 . 



Other papers include : 



Allee, "Note on Animal Distribution following a Hard Winter " (Biol. Bull., 

 vol. xxxvi, Feb. 1919); Allen, "A Technique which Preserves the Normal 

 Cytological Conditions in both Germinal and Interstitial Tissue in the Testis of 

 the Albino Rat (Mus norvegicus albinus)" (Anat. Rec, vol. xvi, March 1919) ; 

 Lund, " Simple Method for Measuring COa produced by Small Organisms " (Biol. 

 Bull., vol. xxxvi, Feb. 1919) ; Pohlman, "The Use of Bayberry Wax in Harden- 

 ing Paraffin Blocks" (Anal. Rec, vol. xv, Feb. 1919) ; "A Modification of the 

 Born Paper-wax Reconstruction Plate," and "The Use of a Simple Method of 

 Recording the Relations in Serial Sections, particularly for Use in Teaching 

 Embryology " (ibid., Feb. 1919). 



ANTHROPOLOGY. By A. G. Thacker, A.R.C.Sc, Public Museum, 

 Gloucester. 



Much interesting matter will be found in the recently-estab- 

 lished American quarterly publication entitled The American 

 Journal of Physical Anthropology, which is edited by Prof. 

 A. Hrdlicka. The first article in vol. ii, No. 1, of this journal 



