Clapp, Allis on Nctves of Ainia. 175 



Review of Allis' Paper on the Cranial Nerves of Amia.^ 

 By Miss Cornelia M. Clapp. 



Mt. Holyoke College. 



Mr. Allis seems now to have accomplished the task set for 

 himself in 1886. This is the third paper which has appeared; 

 the first being the admirable account of the "Anatomy and 

 Development of the Lateral Line System of Amia calva ; " the 

 second, a short paper in '95, preliminary to the third which ap- 

 peared about a year ago. It is, as it was intended to be, "an 

 accumulation of facts and references grouped so as to be con- 

 veniently used as a basis for further work." 



In the eighteen beautiful plates illustrating the paper, Mr. 

 Nomura, the artist, has faithfully reproduced the dissections, 

 many of which were made by himself. 



The thoroughness of the work is indicated from the state- 

 ment in the introduction, that "nothing is shown in the adult 

 that was not controlled in larvae, and everything found in larvae 

 has been sought for until found or accounted for in the adult." 

 The chief merit of this voluminous paper lies in its accur- 

 ate detail, making it invaluable to the anatomist as a reliable 

 source of information. 



From the study of the eye-muscles and their innervation, 

 Allis thinks that the muscles of the eye in vertebrates are not 

 homologous structures, the want of homology being found en- 

 tirely in those muscles that are innervated by the oculomotorius 

 and abducens, i. e. those muscles that are said to arise from van 

 Wijhe's first and third somites. As the eye-muscles have been 

 developed from the muscle masses in these two somites, differ- 

 ent arrangements have arisen in the various groups of Ichthy- 

 opsida. On this basis Mr. Allis has constructed a number of 

 prototypes, and has added another to the forest of genealogical 

 trees. 



^ The Cranial Muscles and Cranial and First Spinal Nerves in Amia calva, 

 by Edward Phelps Allis. Journ. of Morph., Vol. XII, No. 3, 1897. 



