275 
than that it is purely physiological and adaptive, and leads to a 
distinct gain of surface and a consequent increase in the efficiency 
of each and every corpuscle in performing its function, that for such 
a cause has assumed the discoidal form. That such a double vorti- 
cal flux must take place from two opposite poles of a primitively 
globular or embryonic red blood-corpuscle in passing from its 
primitive globular to that of its completed or adult elliptical or dis- 
coidal form is self-evident upon mere contemplation of the geo- 
metrical conditions that must on @ prior? grounds accompany the 
transformation of a semifluid globular mass to the form of a disk 
with rounded edges. If such a vortical flux of its substance were 
maintained by every corpuscle during its double cycle of wander- 
ings through the systemic and pulmonary circulations and through- 
out life, its efficiency in the processes of metabolism must neces- 
sarily be greatly increased. The fact that Amceba cannot move 
without developing a vortical flux of its own substance through 
itself, is, it seems to me, evidence of the possibility and probability 
of the same thing occurring in red blood-corpuscles. If the fore- 
going hypothesis is true with respect to red blood-corpuscles, we 
have no less than ten millions of vortex rings of particles whirling 
together in pairs for every cubic millimeter of blood that circulates 
through the vessels of our bodies. 
A Study of the Transformations and Anatomy of Lagoa crispata, a 
Bombycine Moth. 
By Alpheus S. Packard. 
The larva of this moth is exceptional among caterpillars, for it 
has the rudiments of two pairs of abdominal legs more than the 
five pairs common to all other known Lepidoptera. It is also re- 
markable for its metameric glandular abdominal processes. 
A very full and careful account of the life-history of this inter- 
esting moth has been published by Dr. J. A. Lintner, in his Zx/o- 
mological Contributions, No. ii, p. 139. He describes six stages, 
and gives an interesting account of the cocoon and mode of pupa- 
tion.* 
* See also two briefarticles by myself: ‘‘On the Larva of Lagoa, a Bombycine Caterpillar 
with Seven Pairs of Abdominal Legs; with Notes on its Metameric Glandular Abdomi- 
nal Processes.” Zoologischer Anzeiger, 27. Juni, 1892, pp. 229-234; ‘‘ The Bombycine Genus 
Lagoa, Type of a New Family,” Psyche, July, 1892, pp. 281, 282. 
