On some Species of Sessile-eyed Crustaceans. 75 



equal in length to tlie hand, as in Boeck's account. The Rev. 

 A. M. Norman, to Avhose kindness I am indebted for the means 

 of comparing the foreign literature on the subject of Microdeute- 

 rojDus {Autonoe) longipes^ doubts whether Boeck is really de- 

 scribing the same species as that which Bruzelius woxaQ^ Autonoe 

 loncjipes ; for, while the branches of the last ])leopoda are said 

 bj Lilljeborg to be equal to one anotlier, and by Bruzelius to 

 be twice as long as their stem, Boeck speaks of the outer branch 

 alone as being much longer than its peduncle. On the other 

 hand, the (x«/«??iar«<sZo?i^«2^e.s of Lilljeborg suits the Salcombe 

 species in all respects, if the term " margo posticus " could 

 be understood to mean not what is commonly called the hinder 

 margin, but the palm at right angles to it. In that case the 

 name hidentatus would have to succumb to the priority of 

 longipes. 



It may be added that Boeck is not very consistent in his 

 discrimination of Microdeuteropus from Autonoe. In the 

 generic character of the former he says that the last pleopoda 

 have the inner and outer ^branches almost equal in length. 

 He then gives two species : — M. gryllotalpa [grandimanus^ 

 Bate), in which the outer is a little longer than the inner 

 branch ; and M. anomalus, in which, he says, the branches 

 are equal. In the generic character of Autonoe he tells us 

 that the outer branch is longer than the inner. This, it must 

 be presumed, implies a decided inequality ; otherwise it would 

 be no mark of distinction from the genus Microdeuteropus. 

 Yet of the only two species described, A. longipes and A. plu' 

 mosa, it is doubtful whether the former possesses this cha- 

 racter ; and of the latter Boeck himself says, not that one 

 of the branches is, but that the branches are, twice as long- 

 as their peduncle. So that, if things which are double of 

 the same are equal to one another, this species ought not to 

 be reckoned an Atitonoe, or the generic character of Autonoe 

 must itself be amended, which would be best effected by its 

 reabsorption into Microdeuteropus. 



Anonyx ohesus^ Spence 'Q?d,Q,=Acidostoma obesum^ 

 Lilljeborg. 



An example of this species, not hitherto recorded from the 

 south, was taken at Salcombe on the muddy sand, from which 

 Ophiura hrachiata may be dug at very low tide. The speci- 

 men was salmon-coloured with white markings, the legs and 

 antennas white, the eyes orange-red. 



