ox THE DEVELOPMENT OF LIMULUS LOXGISPIXA. 83 



pressed close too-ether. I'li^y bave a high colinniiar sliape near the 

 ventral median line ; Itnt a« Ave recede from that liiie tliey become 

 almost suddenly low, fiat, and loose, and are lost in loose, scattered, 

 connectixe tissue cells (figs. 52, 58). This thin walled portion 

 becomes the funnel of the gland. 



The coxal gland is at first straight and obliquely directed ; but 

 so<jn afterwards a small axial pcjrtion of it near the median ventral 

 line is bent backwards parallel to the median line makins" almost a 

 right angle witli tlie rest of tlie gland (fig. 14). The apex of the angle 

 is now gradually sliifted forward:- ; the result Ijeing that the angle be- 

 comes more and more acute, as the limbs of the angle increase in 

 length, wliile the distance l)etween their l)ases remains aluKjst 

 constant. The |)osterior end of the internal limb of the gland de\el<j[)s 

 a little downwards and then ))ackwards till it touches the p(jsteri(.)r 

 surface of the c<jxal joint of the fifth ap[)endage, where it is connected 

 with tlie epiblast and inakes the lumen of the gland communicate 

 freely with the exterior. The coxal gland at this stage is represented 

 in fig, 19. Its anterior apex reaches the mesoblastic dissepiment 

 l)etween the third and f jiu-th appendage-bearing segments. Its external 

 lindj is arched externally, the key-stone of the arch being at the meso- 

 blastic dissepiments between the fourth and fifth a[)pendage-bearin('- 

 segments. The Ihnnel is directed outwardly and posteriorly and is in 

 the mesoblastic dissepiment between the fifth and sixth appendage- 

 bearin''' seii'ments. 



In the next stage (fig. 20) the anterior apex of the gland has 

 reached in its gr<jwth the mesoblastic dissepiments between the second 

 and third appendage-bearing segments, and another curvature — this 

 time tcjwards the mesoljlastic dissepiment between the third and fourth 

 appendage-bearing segments — has been added to the external limb. 

 A\'h('n the uland of this sta<i'e is seen from (jne side, its external 



