ELISHA MITCHELL SCIENTIFIC SOCIETY 86 
Dr. Conant’s many friends, well aware of his candid, 
judicial mind, his keenness and persistency in observing 
and in reasoning from observations to a conclusion, have 
entertained the highest expectations of the work he was 
to do for science. Cut off at the beginning of his career, 
he leaves behind him several smaller papers and the dis- 
sertation before us. On closing this volume the author’s 
friends will feel confirmed in their high opinion of his 
abilities, and those who did not know Dr. Conant will 
realize with regret that an able and conscientious natu- 
ralist has been removed from our midst. 
Dr. Conant’s dissertation. published as a memorial vol- 
ume by his friends, fellow students and instructors, with 
the aid of the university in which he had recently taken 
his doctor's degree, deals with the anatomy and classifi- 
cation of one of the most interesting groups of jelly-fish, 
the Cubomeduse. In this group, embracing but a small 
uumber of species, the scyphomedusan structure, with 
which most of us are chiefly familiar through the study of 
Aurelia, Cyanea or Dactylometra, is in general presented 
as destitute of the complications which characterize the 
more common forms. . This simplicity in general struct- 
nre places the groupclose to the stem-forms, 7essera and 
Lucernaria, themselves scarcely more than sexually ripe 
Scyphistomas, and makes a comparison with existing 
Actinozoa an easy matter. Curiously enough, the mem- 
bers of this primitive group possess the most highly de- 
veloped sense-organs as yet describea among coelente- 
rates, the nervous system being correspondingly differ- 
entiated. In one other respect the Cubomeduse are 
unique, in that they alone among the Scyphomeduse pos- 
sess avelum. The phylog-netic origin of this velum 
(velarium) has been the subject of some discussion, the 
balance ot opinion inclining to the belief that it has arisen 
through the fusion of marginal lobes similar to those 
