99 



of them were A. psi, although some few, he thought, were 

 A. tridens. Dr. Chapman said that although no special 

 character could be pointed out for differentiating these two 

 species, it was not difficult to separate them by their general 

 facies. Some of the specimens exhibited were undoubted 

 tridens, but by far the greater proportion of them were with 

 equal certainty ^s?. 



Mr. E. Step exhibited male and female specimens oi Atele- 

 cyclus septemdentatus, Mont., from Portscatho, Cornwall, and 

 said they had been brought up from a depth of twenty 

 fathoms, clinging to the bait on a spiller-line. It is distinctly 

 a deep-water form, and this fact no doubt explains another 

 — that it remained quite unknown to science until the begin- 

 ning of this century, when the indefatigable Colonel Montagu 

 discovered it on the Devonshire coast. Leach described it 

 soon after as being found in plenty in deep water along the 

 south coast of Devon ; but Ed. Parlitt, in 1870, declared it 

 was no longer plentiful there. Couch, in his " Cornish 

 Fauna," says it abounds in between twenty and fifty fathoms 

 of water off the Cornish coast, and that almost every Ray 

 opened for several days in succession had specimens in its 

 stomach, one fish containing as many as thirty of the crabs. 



The species is allied to the masked crab {Corystes cassive- 

 launits), Penn, and, like it, bears a more or less striking 

 human countenance engraved upon the carapace, so that in 

 Devonshire it is known as the " old-man's-face crab." Like 

 Corystes also, it is fitted for living beneath the sand at the 

 bottom, but apparently not so deeply buried. The hairy 

 antennae can be brought together to form a tube for the pas- 

 sage of water to the gills, and the very hairy limbs, when 

 drawn up clo^e to the body, protect the opening along the 

 edge of the carapace into the gill-chamber, so that whilst 

 water may pass readily, grains of sand cannot. The eyes are 

 mounted on long stalks, which enable them to see above the 

 surface of the sand, whilst the crab is hidden beneath. 

 Atelecycliis is apparently an older form, from which probably 

 Corystes has been evolved. 



Mr. Tutt exhibited a few bred specimens of Porthesia chry- 

 sorrhcea, showing traces of the black dot at the anal angle of 

 the fore-wing, which is a characteristic mark of P. siinilis 

 (auriflua). One specimen in particular had the spot well 

 developed, and in addition had a few black dots scattered 

 over the fore-wings. He also exhibited a pair of Laiiipides 

 [Lyccena~\ bcetica, taken in copulation at Fontainebleau, and 

 referred to the abundance of this species in Europe during the 



