268 
Transactions of the 
r.Monthly Microscopical 
L Journal, May 1, 1869. 
significance differing from that of the tail or cihum of the moving 
zoosperms. 
I will commence my description with the zoosperms of Careinus 
Mmnas (Fig. 1), these being the simplest form, consisting almost 
wholly of caput, a small, round, highly refractive particle, having 
the appearance of being solid and hard ; on either extremity is a 
projection, the two being united by a ridge across the caput, as if 
the latter were carried on a rod which transfixed it ; occasionally 
the projection of one side is wanting, in which case the zoosperm 
seems incomplete; the rod is very often curved instead of being 
straight ; there is, in fact, a good deal of irregularity in their forms ; 
they measure in diameter 0*004"^'^; their length, including pro- 
jections, which occupy half the extent, O'OOS'""'. This form 
appears to correspond simply with the caput of other zoosperms ; 
and as there is no cilium, so there is no motion. 
The zoosperms of Maia verrucosa are slightly more compli- 
cated than the last, viz. a round disc, representing the spherical 
Fig. 8. — 6. same after remainirig some time soaking in the blood of the animal ; 
largest nucleus measures 0 • 010""™, smallest 0 * 008™«. 
c. smaller cells ; largest 0* 010"™, smallest 0' 008""". 
d. cells with smooth nuclei. 
e. „ rod-like nuclei. 
/. „ double rod-like nuclei. 
g. „ „ granular nuclei. 
A. „ amoeboid movements. 
„ 9. — a. Cells from testis treated with water. 
h. cells treated with liq. potasste. 
c. „ „ acid acet., granular nucleus. 
^« ■>■) y •)•) 5> 
^' 11 11 11 11 
10, — a. Smaller cells from testis of P. Bernhardus, measuring 0*010 long and 
0-007 broad. 
6. cells with external nuclei, a. nucleus ; /8. cell. 
c. „ a. with smooth nuclei and vacuoles; 0. vacuoles have 
disappeared, leaving the centre of the cell empty. 
„ 11. — Mature zoosperms to which water has been added, 
a. commencing. 
h. full effect. 
a. caput ; fi. tail. 
Plate XII. 
Fig. 12. — Transition stage between cells and zoosperms. 
a. cells with refracting nuclei ; length 0*008, nucleus 0*005. 
6. triangular bodies resembling the caput of mature zoosperm ; 
0 • 007 ™™ broad, 0 * 006 ™™ long. 
J J 13. — Cells from testis of 8. Longirostris ; largest measures 0*010 in. diameter. 
14. _a. Cells from testis of lobster ; 0 * 020 ™™ ; nucleus 0 * 013 
6. cell with external nucleus; 0*016 long, 0*011 broad. 
c. stellate body ; the third lay is not visible in this specimen. 
15. — Commencement of spermatophorum of P. Bernhardus ; three sections with 
dividing dislocations shown in figure. 
16. — Succeeding stage ; small parcels of zoosperms are seen between some of 
the young spermatophora. 
„ 17, 18, 19.— Subsequent stages of development of spermatophora. 
