308 Remarks on the Impregnation of Plants. 
uth apparatus—aba! upper limits of lower liprste! the extremities 
of the transverse bony arch—de, bone which curves ate and passes towards the 
base of the maxilla—f, f' maxille, the lower extremities of which are beneath the 
lower lip. 
Fig. 5. g,g’ internal bones connected with the maxille f,f' and situated in the 
animal as here represented. 
Fig. 6. One of the jointed bony rays of the suction legs. 
Fig. 7. First pair of natatory legs, exhibiting the two terminating pinnule, of 
which one is jointed at its extremity, and also the recurved pinnula, jointed near 
its middle—also the ridges of hairs which in the animal are represented near the 
posterior margin of the legs. . These hairs are perspectively foreshortened, 
Fig. 8. Particles observed in the circulating fluid. 
Fig. 9. Back view of the Argulus Catostomi, the right hand side exhibiting 
the circulation, the left hand, the mascles which move the mel panies oraeys 
below as seen through the transparent parts above—i, i, the an ary current— 
n, the a. current of the same—h, the ophthalmic, (seen most distinctly belay 
k, eee 5 m, lateral current whose direction is pointed out by the arrows they 
tion om et the shell with the abdomen. On the left, i,0,k, m, represent four muscles 
by which the waka moves its shell. Three of the blood iin above pointed 
out, i, k,m, are in the direction of these muscles—i,i, move clypeus—o, @ 
portion of the sell between the.clypeus and x—k, and m, the ica and posterior 
parts of the sa 
1 Under view of the young a the Argulus Catostomi. 
’ Fig. 11. shcoeetocin of the legs corresponding to the suction legs in the per- 
eget hag pine partly separated hein its sheath. 
Art. XIX.—A Translation of a memoir entitled “ Beitrage zur 
Lehre von der Befruchtung der Planzen,” (Contributions to the 
doctrine of the impregnation of plants;) by A. J. C. Corpa: 
published in the 17th volume of the Nova Acta Physico-medica 
Academie Cesar. Leopold.-Carol. Nature Curiosorum. Breslau 
and Bonn, 1835 ;—With prefatory remarks on the progress of 
~ discovery relative to vegetable fecundation; by Asa Gray, M.D. 
ee : 
Read before the Lyceum of Natural History, New York, Oct. 24th, 1836. 
Tue last volume of the transactions of the Imperial Acad. Nature 
Curiosorum, just received through the kindness of the learned Nees 
Von Esenbeck, the president of that society, contains a brief memoir 
on the impregnation of plants, which will doubtless be read by the 
botanist and the physiologist with more than ordinary interest. M. 
Corda, in the paper referred to, gives an account of an original and 
highly curious series of observations on the structure and develop- 
ment of the ovules, and the mode in which i impregnation is effected, 
in the natural family Conifere. The memoir is illustrated by nu- 
merous admirably executed figures. 
tom 
