Turner, The Nn-7'o?is System of Cypris. 37 



In contrast with the above, the ventral chahi of Halocypris 

 appears much concentrated. It consists of an infra-oesophageal 

 ganghon with nerves to the jaws and maxillipedes, and a small 

 ventral ganglion. Out of the latter arise two pairs of nerves, 

 which probably innervate the musculature of the limbs and the 

 abdomen." 



Morphologically the ventral chain of Cypris Jicrricki 

 Turner, is intermediate between these two extremes. It is 

 more concentrated than that of Cythcre but not quite so com- 

 pact as that of Halocypris. In this case the ventral chain con- 

 sists of an infra-oesophageal ganglion and two subsequent ven- 

 tral ganglia. All these ganglia are connected not only by two 

 longitudinal commissures, [fig. 7] which extend throughout the 

 chain, but also by straggling chains of cells [fig. 9]. 



The infra-oesophageal ganglion is compounded out of three 

 pairs of ganglia and innervates the jaws and maxillae. Three 

 transverse commissures can be demonstrated in this compound 

 ganglion corresponding to its three pairs of nerves; viz. the 

 mandibular and the two maxillary nerves. The mandibular 

 nerve arises in the cephalic portion of the infra-oesophageal gan- 

 glion. It passes forward into the circum-oesophageal commissure 

 for a short distance and then passes laterad to the mandible, 

 [fig. 3] A short distance caudad of the mandibular nerve the 

 first maxillary nerve leaves the infra-oesophageal ganglion and 

 passes laterad to the first maxilla, [fig. 7] Still further caudad 

 the second maxillary nerve leaves the infra-oesophageal ganglion 

 and passes latero-caudad to the second maxilla, [fig. 7] In ad- 

 dition to these nerves, in some of my sections I have observed 

 what appears to be a nerve passing to the digestive tract. If 

 this be a nerve (which I doubt) it may be a representative of the 

 sympathic system. 



The two ganglia which follow the infra-oesophageal ganglion 

 correspond to the two pair of legs which follow the maxillae. 

 From the lateral borders of each ganglion nerves pass to the 

 corresponding pair of legs. In addition to this, from the last 

 ganglion a prominent tract passes caudad to innervate the pos- 

 terior portion of the body and the post-abdomen. As this tract 



