APPENDIX. 



A..-OJir ARTEMIA FERTILIS VEEEILL, FROM GEEAT SALT 

 LAKE, UTAH TEEEITORY.^ 



By Pkof. C. Th. von Siebold, of Munich. 



[Translated by Dr. Phil. Carl F. Gissler, of Providence, E. I.] 



Having positively convinced myself several years ago thut Artemia 

 salina, which is known to inhabit in countless numbers shallow brackish 

 ■water ponds along the shores of Europe, in those localities propagates 

 parthenogeneticaily without males,^ I put to myself the question 

 whether this was also the case with other species of the genus Artemia. 

 To solve this problem I conceived the idea of procuriug live specimens 

 of the brine shrimp from the Great Salt Lake of Utah, which 1 knew 

 to occur there in both sexes and in great numbers. The middle of 

 March this year (1876) I obtained, through the kindness of Dr. Hermann 

 A. Hageu, of Cambridge, Mass., a considerable quantity of dried mud 

 from the Great Salt Lake, with which I experimented in the following 

 manner: Toward the end of Mar(;h, of the same year, I divided some 

 of the dried mud into several shallow glass jars, pouring over it on the 

 6th of April artiiiciany prepared sea-water, using common hydrant- 

 water and Eeichenhaller brine. On the 8th day of April already the 

 water in one of these jars sw^armed with Nauplii, the hatchmg of which 

 I eagerly watched, as I observed many brown Artemia eggs on stirring 

 up the mud infusions. The brood prospered excellently, the mud being 

 evidently impregnated with organic matter, the latter serving as food 

 during their different moults and stages of development ; and already 

 on April 16, about eleven days after hatching, indications of sexual 

 characters could be perceived, in the male sex perceptible by a stouter 

 swelling of the claspers. This sexual character, after which the dif- 

 ferentiation of the organs of reproduction appear, refers to the organs 

 of copulation only, and not to the true fructification organs, and was 

 for my experiments of great importance. This early dilterentiatiou of 

 the male and female individuals of Artemia fertilis gave me occasion to 

 distinguish the males from the females, and to keep them separate al- 

 ready at a time before the internal sexual organs, the testicles of the 

 males and the ovaries of the females, began to develop. The second 

 pair of legs of the six-footed Nauplius is, after the first moult, i)romi- 



'Ueber die in Mtinclien geziichtete Artemia fertilis ans dera grossen Salzsee von 

 Utah. Vou Prof. C. v. Siebold in Miiuchen. Separatabdruck aus den Verbandlungen 

 der 5'Jten Jahrcsversammlung der Schweiz. naturf. Gesellscbaft in Basel, 1876. Basel, 

 1877. 8°. pp. 16. 



So mncb that is of great interest in connection with the doctrine of evolution and 

 of parthenogenesis has been published regarding the Phyllopods, that we avail our- 

 self of the kind permission to insert, as an appendix, the most imjiortant papers which 

 have appeared. I am indebted to Dr. C. F. Gissler for this and the following transla- 

 tions and abtracts. 



2 See my lecture on " Parthenogenesis of Artemia salina," in the Sitzuugsberichte 

 der mathematisch-physikalischen Classe der K. Akademie der Wisseuschuften, of 

 June 7, 1873, p. 168. 



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