found in the Firth of Forth, 367 



The habits of this animal are extremely active, and are very 

 similar to those of the Dapknia. This species, along with 

 different Entojuostraca, forms the principal food of the her- 

 ring during the summer months. 



section iii. on a new genus of pycnogonid^. 



Genus Pasithoe 



Forms a new type among the Fycnogonidw, Its generic 

 characters are very distinct. The rostrum is very long, and 

 is armed on either side with a long and powerful palpus, whicli 

 is composed of eight articulations. No mandibles. Oviferous 

 legs very short, and nine-jointed. 



p. VESICULOSA. {Mlhi.) Plate VI. fig. 17. 



Description. — The whole animal is of a brown colour. The rostrum is 

 oblong, oval, contracted at either extremity, and considerably swollen 

 in the middle. The palpi are eight-jointed, rather longer than the ros- 

 trum, and are armed at their extremities with long hairy spines. Tise 

 three coxal joints of the ambulatory legs are minute ; the second one 

 is considerably dilated at its distal extremity. The femoral and t\YO 

 tibial joints are all equal in length, and each of them is peculiar in 

 shape ; about one-third of its proximal extremity is very much con- 

 tracted, and quite cylindrical ; the succeeding portion then swells sud- 

 denly out, and is rounded off at its distal extremity. The first or con- 

 tracted portion of these joints is apt to be mistaken for a separate arti- 

 culation. The first tarsal joint is minute and rounded ; it is only seen 

 from the lower surface. The second tarsal joint is equal in length to 

 the femoral or tibial joints, and is very much bent, and its extremities 

 armed with the usual number of claws ; but the two auxiliaries are 

 very minute. The first thoracic segment of the body is the largest, 

 being as large as the three others combined. The oculiferous tubercle 

 is situated near the anterior edge ; it is small, and the eyes are placed 

 around it. The last or abdominal segment is very long and slender, 

 being almost as long as the rostrum ; it ends in a fine point. The ovi- 

 ferous legs are very short ; the fifth joint is longest. Span of legs 

 half an inch. 



This animal approaches more nearly to the genus Pycnogo- 

 num than any other species of the family yet known ; and, at 

 the same time, many of its characters assimilate it to the genus 

 Phoa:ichilus ; thus, I should think, forming the connecting link 

 between these two genera. 



