86 MCaMURRICH. [Vol. XI. 



one sees that the cells of the anterior portion of the body are 

 arranged very irregularly, but form three bands which enclose 

 a triangular area whose apex is directed backwards and whose 

 cells are scattered about irregularly. The two bands which 

 form the sides of the triangle are the ventral lateral bands 

 which have been so often figured in the early stages of the 

 Decapods and in which the naupliar appendages and nervous 

 system will form, while the transverse band forming the base 

 of the triangle is apparently not so well marked in the Deca- 

 pods, though evidently distinct in AlpJiciis according to Her- 

 rick's ('92) figures and descriptions. At the basal angles of 

 the triangle are the " Anlagen " of the eyes {E). This anterior 

 region represents then the naupliar region of the embryo, and 

 behind it comes what has been termed by Bergh ('92) the meta- 

 naupliar region, whose ectoderm is markedly arranged in rows 

 and has resulted by the growth of the teloblasts. Examining 

 the anterior portion of this region, one finds that there are 

 about eleven rows of cells which extend farther forwards than 

 the others. In the embryo figured there seemed to be only 

 ten of these longer rows, but this seems to have been an 

 abnormality if it can be so called, eleven being probably the 

 typical number. Further back other rows are to be found on 

 each side, those nearer the middle line being longer than those 

 further laterad. At the end of each row is a teloblast (Fig. 

 25, T) slightly larger than the other cells of the row and 

 frequently showing karyokinetic phenomena. The number of 

 teloblasts and accordingly of the rows is liable to a certain 

 amount of variation apparently. A central teloblast with its 

 row is generally well marked, as may be seen in Fig. 26 {cT) 

 drawn from a somewhat older embryo than Fig. 25, and it may 

 be stated here that the cell row arising from this gives rise to 

 a " Mittelstrang " recalling what has been described in other 

 Invertebrates. On each side of this central teloblast there are 

 about eleven or twelve lateral teloblasts, there being typically 

 the same number on both sides, though not infrequently one 

 finds, for example, eleven on one side and twelve on the other, 

 as in Fig. 26. Behind the teloblast row is a varying number 

 of ectoderm cells arranged somewhat irregularly. They are 



