The development of Fundulus heteroclitus in solutions of lithium chlorid, with appendix on its development in fresh water

resulted, although Gurwitsch concluded that his radial larva was the specific result of the lithium action.Morgan then in 1902 carried on experiments to test the effects of LiCl on frog's eggs, and again in the following spring he used a number of lithium salts along with other solutions for comparison.He finally concluded that lithium produced in the development of the frog's egg a typical larva just as Herbst had shown for the sea-urchin.Both of these workers claimed for similar reasons that the effect was due to the chemical action of the lithium ion and not to osmotic or pressure effects; hence the specific character of the embryos.Loeb, Mathews and others have subjected the eggs of the fish, Fundulus heteroclitus, to solutions of lithium salts, but only to observe the physiological effects of the solutions, ignoring the morphological changes induced.With these results in view Prof. T. H. Morgan kindly suggested that I study, from a morphological standpoint, the effects of lithium salts on the fish's egg.It is, therefore, a pleasure to avail myself of this opportunity of expressing my indebtedness to Professor Morgan for his kindly advice and criticism throughout the progress of this work.T h e experiments were conducted during the past summer while occupying a table in the United States Fish Commission Laboratory at Wood's Hole, and I wish to thank the authorities of this laboratory, particularly the director, Dr. F. B. Sumner, for the courtesies extended me while there.T h e Fundulus egg differs in its mode of development from both that of the sea-urchin and the frog, hence it is of interest to note whether or not an effect such as that produced by lithium is at all comparable in the three cases.Of course it is fully realized that no strict embryological comparison should be made among types of development so different as these, yet one may find little objection to a comparative study of the chemical effects produced in the three widely different forms bv one and the same element, lithium.At present I am not in a position to state that the abnormalities which have been induced in the Fundulus egg by means of LiCl are specific for lithium, as a number of other salts must first be experimented with.T h e abnormalities described are not exceptional, but general, occurring in as large a per cent.