1G? CANON A. M. NOEMAN ON A CRUSTACEAN 



CIRRIPEDIA. 



Order ASCOTHORACICA. 



Family Stnagogid.e, Gravel. 



Synagoga mira, Norman. 



In 1887, when working at Naples, Signor Lo Bianco brought me some parasites in 

 spirits which he had found on the Actinozoan Antlpathes larix, Esper. The parasites 

 were external and had all been removed from the host to which they bad been attached. 

 These most interesting parasites I briefly described in the British Association Report 

 fur 1887 (1888), p. 86, under the name Synagoga mira. I purposed to write a full 

 account of this species shortly afterwards, but I delayed doing this in the hope of being 

 able to procure the earlier stages of development, which I had requested Signor Lo 

 Bianco to kindly look out for me ; these, however, he was unable to procure. About 

 two years ago, finding that my material was not sufficient to clear up certain points 

 connected with the sexual characters, I wrote to Br. Giesbrecht to ask him if he could 

 procure for me some further, and fresh, specimens of the species. He has now written 

 me to say that, although he has examined such specimens of Ant i pat lies and Isis as bad 

 come into the Station, he has not been able to meet with Synagoga. He tells me that 

 the two genera just mentioned are much scarcer in the Bay than they used to be ; he 

 adds that " Synagoga has not been found in the Bay of Naples since the time that you 

 described it." It would seem, therefore, that tbe species must be extremely rare. As 

 long ago as 1890 I had a series of illustrative drawings made for me by Mr. A. Scott ; 

 a few additional drawings have been made by Mr. E. Popple. 



The Synagoga is enclosed in a mantle or sheath in form as the bivalve of Cypris or 

 Estheria. This enclosing sheath is nearly ovate (PI. 33. fig. 1), somewhat narrower in 

 front, where it is slightly ernarginate above; its measurements when full-grown are 1 mm. 

 in length and 3 mm. in breadth ; the external surface is covered with minute triangular 

 spinules which are somewhat larger towards the margins ; the eggs are contained in 

 ovaries within the sheath. The animal itself is attached by two very strong bundles of 

 muscles to the upper portion of the sheatb, and with this exception enjoys perfect 

 freedom of motion ; it is rarely withdrawn wholly within the sheath. 



The body consists of a cephalon, furnished with very large and strongly developed 

 antennules (PL 33. fig. 2), very prominent buccal mass, and the peculiar organ hereafter 

 to be described. The mesosome or body is composed of six segments bearing six pairs of 

 legs. The metasome or tail is five-jointed, of which the first is the genital segment ; this 

 is followed by three segments without appendages, and the fifth which carries distally 

 a pair of serrated spines and two large un jointed rami, which remind one of the same 

 organs in Nebalia bipes. 



The antennules (PI. 33. figs. 2 & 3) take the form of grasping-organs of remarkable 

 size and strength, strong muscles also uniting the several joints. The first joint is about 



