l'(jt Miscelhnjrnus. 



lifc-liistories exhibit a most surprising: lack of agreement. In fact, 

 tho early stages in (ho life of Aljiheus heicrochells in tlic Bahama 

 Islands ditfer mucli less from those of Aljiheus minor or Alpheus 

 yormani than they do from those of the North Carolina Alpheus 

 heterovhtlis ; and, according to Packard, the Key West heterochelis 

 presents still another life-history. 



In the summer of 18S1 I received the * American Naturalist' with 

 Packard's veiy brief abstract of his observations at Key Wcbt upon 

 the development of Alpheus JuterocJielin, and read with great surprise 

 his statement that this species has no metamorjjhosis, since, while 

 still inside the egg, it has all the essential characteristics of the 

 adult. As I had under my microscope at Beaufort on the very 

 day when I read his account a newly hatched larva of tl>o same 

 species and was engaged in making drawings to illustrate tho meta- 

 morphosis of which he denies the existence, and as my experience 

 in the study of other Crustacea had taught me that all the larviu of 

 a species at the same age are apparently facsimiles of each other 

 down to the smallest hair, Packard's account seemed absolutely 

 incredible, and I hastily decided that, inasmuch as it was without 

 illustrations and was vrritten from notes made many years before, 

 it involved some serious error and was unworthy of acceptance. 

 This hasty verdict 1 now believe to have been unjust, since my 

 wider acquaintance with the genus has brought to my notice other 

 instances of equally great diversity between the larvae of different 

 specimens of a single species. 



The phenomenon is, however, a highly remarkable one and 

 worthy the most thorough examination, for it is a most surprising 

 ileparture from one of the established laws of embryology — the law 

 that the embryonic and larval stages of animals bfst exhibit their 

 fundamental affinities and general resemblances, while their specific 

 characteristics and individual peculiarities make their appearance 

 later. — Am. Journ. Set., Feb. 1893, pp. IGO, IGT. 



Ahsorption in the Actinia; and the Or!r/in of the Mesenterial Filaments. 

 Bj- Victor Willem, Assistant in Zoology at the University of 

 Ghent. 



If albumen stained with carmine is administered to specimens of 

 Actinia or Sayartia it is found that at the end of a icvf hours 

 particles of carmine arc present in the cells of the lining of the 

 enteric cavity. Properly speaking this absorption does not take 

 place in the enteroids, as is stated by Krukenberg * and Metschni- 

 koff t, but at first and chiefly in the region of the radial partitions 

 which adjoins these filaments, a region where the epithelium forms 

 a thickening parallel with the edge of the septum % ; the grains of 



• Krukenberg, " Ueber den Verdauungsmodus dcr Actinien," Vergl.- 

 pliys. Studien an dor Kiiste der Adria, 1 Abth., 1880. 



t Metschnikoir, " Ueber die intracellulare Verdauung bei Ccelente- 

 raten," Zoul. Anz. 1880, p. 201. 



t Vide Hertwig, " Die Actinien," Jenaische Zeitschriff, 1879, Taf. xxi. 

 6g. 13. 



