EOLIS CORONATA. 



and a half in length. It may be distinguished by the brilliant blue which is always more or less 

 present on the branchiae, sometimes only giving them a faint tinge, at others forming a 

 streak down the front of each papilla ; and sometimes a very beautiful variety occurs with 

 the blue nearly covering their whole surface. The branchiae are variable in number and 

 liable to fall off. An entire clump is sometimes wanting. 



This is a very active animal, and whilst gliding forward its tentacles are in continual 

 motion, bending gracefully in all directions. Both pairs appear to be endowed with great 

 sensibility, contracting themselves and suddenly shrinking backwards on coming in contact 

 with anything. Sometimes they will do this without apparent cause. The branchiae, too, 

 usually partake of this restless motion, and are capable of great extension and contraction 

 at the will of the animal. We have had several opportunities of noticing the carnivorous 

 propensities of this species, which is certainly not the least voracious of its tribe. After 

 having been for a day or two without food, they will even devour their own kind, the weaker 

 falling a sacrifice to the cravings of the stronger. Large individuals will content themselves 

 with plucking off each other's papillae ; but should a smaller specimen be within reach, it is 

 most mercilessly attacked, the more powerful animal laying hold of any part of the weaker 

 that may happen to be nearest. The tail, however, is generally first seized, and fierce and 

 determined is the onset. The devourer raises and shakes his papillae in the manner that the 

 porcupine shakes its quills when irritated, and then, laying back the dorsal tentacles and 

 curling up the oral ones, fixes the protruded mouth and jaws upon his prey, when, with a 

 convulsive shrinking up of the body, morsel after morsel is appropriated. In this manner 

 it is not uncommon to see an individual entirely devour another, half its own size. We have 

 also seen this species feed upon a Lucernaria. 



Eolis coronata spawns most abundantly in June, at which period it is rather plentiful 

 among the rocks at Whitby and Cullercoats ; patches of spawn, however, are not unfrequently 

 found in July, and occasionally in August. The spawn is attached to the underside of 

 stones, and is disposed in a close-set spiral coil of four volutions, consisting of a waved 

 gelatinous thread, with yellowish imbedded ova. 



This species was first discovered by Professor E. Forbes in Shetland, and we have since 

 found it in several places ; principally on the northern shores of our islands. On the 

 Northumberland coast it is one of the most common species, and in Malahide Bay we found 

 an orange variety of it in considerable numbers on large Laminarice and sponges dredged 

 in shallow water. 



We suspect that the Eolis peregrina, mentioned by Dr. Grant as having been found in 

 the Frith of Forth, is this species, which somewhat resembles that of Cavolini in the colour 

 of the branchiae, but not in their arrangement. We see no good reason for believing that 

 the true IE. peregrina has ever been found in this country. 



The pulsations of the heart are about sixty-five in a minute. 



Fig. 1, 3. Back and foot views of Eolis coronata. 



2. Side view of the blue variety. 



4. Two of the papillae more highly magnified. 



5, 6. Dorsal tentacles. 



7. Spawn. 



8. A portion of the same more highly magnified. 



9. Two teeth from the tongue highly magnified. 



