BIOGRAPHICAL SKETCH li 
the history of the marginal cells led to the solution of ‘‘one of the 
cardinal questions in the early development of the teleostean 
fishes, namely the precise origin of what His and others have called 
the ‘parablast.’”? The authors showed that the nuclei of the peri- 
blast, as they termed this layer, are derived entirely from the mar- 
ginal cells of the blastodisc, and the fallacy of “‘free cell-forma- 
tion’? and of separate origin of the ‘‘parablast and archiblast’’ 
thus received its quietus. Their hope that a similar result would 
be reached for other meroblastic vertebrate ova has since been 
realized. 
Leeches 
Professor Whitman’s interest in the Hirudinea, aroused and 
fostered during his occupany of a table in Leuckart’s laboratory 
at Leipzig, continued unabated until his labors were so tragically 
terminated. That this interest was no narrow one, but traversed 
much of the depth as well as the length and breadth of biological 
science, is much less apparent from a list of the titles of his papers, 
than from a perusal of their contents. Under such unassuming 
titles as ‘‘The Leeches of Japan,” or “Description of Clepsine 
plana,’ we find treated, not merely specific and faunal details 
but the much larger questions of the formulation of a new system 
for standardizing specific descriptions, the morphological basis 
of generic groupings and the origin, evolution, ecology, adapta- 
tions, morphology, classification and paths of dissemination of the 
land leeches. The latter small group of animals particularly 
appealed to his naturalist’s spirit, not as the disgusting pests that 
they had seemed to most previous describers and tropical travelers, 
but as the keen-sensed, facile winners in a competitive struggle 
for life that must have been of the utmost severity for animals 
that have departed so widely from the habits and environment 
of their ancestors. 
Although Professor Whitman’s contributions to the adult 
morphology of the Hirudinea were not numerous, numbering 
only three major papers and seven or eight preliminary sketches, 
polemics and reviews, they have exerted a great and lasting influ- 
ence. ‘Taken together they form an exhibit of the catholicity of 
his interests and exemplify the soundness of his scientific ideals. 
