THE MOUNT DESERT EEGION 13 



Length: Male, 1.1 mm.; female, 1.5 mm. 



Type : Male, B 134 ; paratypes, B 127. 



Remarks : This species shows a certain resemblance in 

 general aspect to C. jonesi and to C. miicronata. Both of 

 these species have the processes composing the ventrolateral 

 fin separated in the adult and joined by a lamella in the 

 young. Hence C. inexpectatus may be considered ancestral 

 to the C. jonesi group. The other species have the general 

 surface ornamented by mucronate processes, which are want- 

 ing in C. inexpectatus. 



Cythereis procteri spec. nov. (fig. 6) 



The shell is rather thin with a reticulate surface. Each 

 areole has one or two short hairs within it. There is a ven- 

 trolateral row of small blunt teeth extending about half the 

 length of the shell at the middle. The posterior half of the 

 dorsal margin bears three small teeth. The usual posterior 

 and anterior teeth and hairs are present. 



The penis has the terminal part subtriangular and large 

 relative to the basal portion. 



Length: 1.05 mm. 



Type: Male, B 169. 



Remarks : It gives me great pleasure to name this species 

 for Mr. AVilliam Procter, the Director of the Biological Sur- 

 vev of the Mount Desert Region. 



