90 General Notes. | January, 
ing and the disappearance of the chlorophyll almost colorless i 
A. S. Packard, Fr. 
November, 1882, the discovery that Penæus, a Decapod, passes € 
through a Nauplius stage. Those familiar with the literature af | 
the subject will recollect that Fritz Miiller kept under observation 
until it changed into a Protozoéa, a Nauplius which he captured at 
complete series of larvae, through which he identified the Proto 
zoéa with a young Macrouran with the characteristics of the genus 
Penzus. During the past summer, at the marine labratory of Johns _ 
C., Protessor 
stage which Müller actually reared from the Nauplius.” p nave 
had the good fortune to rear this larva in the house, and to witness 
in isolated captive specimens every one of the five molts between 
the first Protozoéa and the young Penzus. a 
“Our boat is too small for work outside during the windy | 
months of June and July, and as the ripe females do not come into 
o M 
coal 
the inlets and sounds, I have not been able to obtain the eggs 0f 
the newly hatched young; but this is the less important, as Fritz 
Müller reared his first Protozoëa from a Nauplius, so that we 
have the entire metamophosis from actual observation.” 
[In 1871 we visited Charleston, S. C., partly for the purp 
of working upon the development of Penzus. Unfortunately 9 
visit, which was early in April, was too soon to enable us to AMY 
the prawn with eggs. None of those brought to the Charlest 
markets in April were spawning. We were informed that- 
prawn does not have eggs until May, probably the latter 
the month. The negroes catch them with sweep-nets.—4. 
Packard, Fr.) “i 
THE GROWTH OF THE MoLLuscAN SHELL.—The structure oft 
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only by study of the first steps. To this end, edges of the 5? 
were snipped away and a thin glass circle thrust between the 4 
mal and its shell, care being taken to prevent injury to the manir 
After the lapse of twenty-four hours the shell was opened and 
glass circle carefully examined, others were allowed to remain t 
days, or three days, or for periods of weeks. 3 
_ In twenty-four hours it was found that a film had been left 
the circle ; in forty-eight hours, this film was plainly stony. 
