94 



Bashford Dean Memorial Yolume 



Bdellostoma during the late fall and early winter in stages which enabled him "to extend 

 the known season of ovulation throughout the entire year." Dean stated, however, that 

 the last of spring and the first month of summer represented a time of optimum spawning. 



The Schreiners (1905, 1908) collected females of Myxine glutinosa containing nearly 

 ripe eggs or fresh corpora lutea, and males with ripe or almost ripe spermatozoa at all 

 seasons of the year. They concluded, therefore, that the deposition of eggs is not limited 

 to any special time in the year. 



While collecting Bdellostoma stouti in California in 1899 and Bdellostoma hurgeri in 

 Japan in 1900 and 1901 Doctor Dean recorded in his notes many observations which 

 contribute toward answering the question of the spawning time. The most significant of 

 these data he incorporated in a graph which he left with his notes and drawings. This 

 graph is reproduced here. 



Text-figure 1. A graph drawn by Doctor Dean to show the data contained in Table II. 



The graph is an illustration of the data contained in Dean's Table II (p. 81); the 

 percentages in the graph and in the table correspond exactly, with the single exception 

 that the figures for July 18, 1900, and July 25, 1901, are interchanged in the case of both 

 the heavy solid line and the heavy broken line (short dashes). In the graph Dean has 

 used the name Hoynea instead of Bdellostoma. 



The abscissa represents the various months of the year, shown in Roman numerals; 

 the vertical lines represent the dates of fishing trips as shown in Table II, beginning with 

 July 18, 1900, at the left and ending at the extreme right with July 25, 1901 . The ordinate 

 represents percentages, written in arabic numerals. 



.The graph shows data for H. stouti, collected in California in 1899, for the months 

 of July and August only. The double line in the upper left corner of the graph represents 

 the percentages of males to the total number of specimens of H. stouti caught during July 



