Septembee 16, 1904.] 



SCIENCE. 



367 



a worthy eontinuer of his work, inspired 

 with his ideas and his method. 



' ' We believe, therefore, that the Physico- 

 mathematic Society of Kazan may legiti- 

 mately decree to him the Lobachevski prize. 

 —P. Mansion." 



To Professor Hilbert I am particularly, 

 personally indebted. My 'Rational Geom- 

 etry' is an attempt to give every teacher, 

 every scholar the benefit of coming after 

 him, the priceless advantage of living since 

 the outpouring of his genius. 



Monsieur Barbarin has honored me with 

 his genial friendship. 



I suppress the temptation to institute 

 comparisons or discuss a decision. 



George Bruce Halsted, 

 Membre d'honneur du Comite 

 Lobatchefsky. 



TBE TROPHOBLAST : A REJOINDER. 



The name Trophoblast was used for the 

 first time by me in the meeting of the 

 Anatomical Congress at Wiirzburg in 1888, 

 and its earliest definition is found in the 

 report of that meeting in Nos. 17 and 18 of 

 the Anatomisclier Anzeiger, Bd. III. We 

 there read, concerning a very early stage 

 of the hedgehog (p. 510) : 



"Die aussere Wand der Keimblase ist 

 verdiekt (drei bis vierschichtig) und be- 

 sitzt wabige Lacunen. Fiir diese aussere 

 (epiblastische) Schicht sei der Name Tro- 

 phoblast gewahlt. " 



In a footnote we find in addition (p. 

 511) : ■ 



"Es ist meiner Ansicht nach zweck- 

 massig, sieh bei der Saugethier-embryologie 

 diesen Namen zu wahlen, um damit den 

 nicht zum Aufbau des Embryos verwendet 

 werdenden Epiblast anzudeuten * * *." 



It is evident from the citations here 

 given that the names outer epiblastic wall 

 .of the mammalian blastocyst and tropho- 

 blast are synonyms. Later researches have 



been directed towards the question how in 

 other mammals than the hedgehog the 

 separation between the epiblast of the em- 

 bryonic shield, i. e., the formative epiblast 

 and the trophoblast, comes about. 



In the same Bd. III. of the Anatomischer 

 Anzeiger, on p. 907, mention is again made 

 of the hedgehog's ' geschlossene Tropho- 

 blastblase (wie ich den primaren Epiblast, 

 von dem sich durch Abspaltung der Epi- 

 blast des Pruchthofes nach innen abhebt, 

 zu benennen vorschlug).' 



Again, in the article on the placentation 

 of Erinaceus in Vol. 30, Pt. 3 (1889), of 

 the Quart. Journ. of Microsc. Science, 

 where the definition was reproduced, it is 

 insisted upon (p. 298) that "the use of the 

 name trophoblast will render unnecessary 

 such circumlocutory expressions as 'outer 

 epiblastic layer of the blastocyst,' 'primi- 

 tive exoehorion,' etc." Further argu- 

 mentation on p. 299, in which the allan- 

 toidean and the omphaloidean trophoblast 

 is defined, leaves not the faintest doubt as 

 to what the name trophoblast has originally 

 stood for. 



Five years later (1894), in an article, 

 'Spolia nemoris,' which appeared in Vol. 

 36 of the Quart. Journ. of Micr. Science, 

 I again insisted (p. Ill) that 'new and 

 valid reasons are ,thus accumulated for 

 designating the outer layer of precociously 

 segregated epiblast cells that form the wall 

 of this vesicle [the early mammalian blasto- 

 cyst] by a separate name, [for which] I 

 have proposed the name of trophoblast.' 

 Somewhat further is added (p. 112) : 'in 

 Tupaja and Tarsius portions of the tropho- 

 blast undergo very active proliferating 

 processes preparatory to the placentary 

 fixation of the blastocyst, whereas in my 

 former papers I have described the same 

 activity for Erinaceus and Sorex.' 



Finally, in 1895 (Verhandl. der Kon. 

 Akad. V. Wetenschappen te Amsterdam, 

 Vol. IV., No. 5, p. 18), I reaffirm that: 



