MUSEUM OF COMPARATIVE ZOOLOGY. 269 



neus shows that Echinoneus has no affinity whatever with the Galeritidae, 

 with which the genus has always been associated, but that it is a true em- 

 bryonic Cassidulus allied to Echinolampada? and Caratomus, already sug- 

 gested by Desor to be a true Cassidulus, and not a Galerites. This affin- 

 ity the examination of young Echinolampadoe proves undoubtedly. The 

 removal of Echinoneus, Caratomus, and all the allied edentate forms of 

 Galerites now reduces the family to one of great homogeneity, and suggests 

 again the question of their affinity to true, regular Echinoids in a more for- 

 cible manner than before. We must, however, wait till we find a living 

 representative of Galerites, to have the question fully decided. I am 

 inclined, in the mean while, to associate the Galeritida? having teeth with the 

 true Echinoids, and consider them as forming among Echinoids a prophetic 

 type of the Clypeastroids, with which they have many points of resem- 

 blance. 

 Littoral. 



Echinolampas caratomoides A. Ac, nov. sp. 



Fragments of an Echinolampas were dredged in the first expedition, in- 

 dicating the presence of a species which must attain a length of at least two 

 inches. In the second expedition an entire specimen, measuring a little 

 over an inch, was dredged from a depth of thirty-five fathoms. H resembles 

 in outline E. Richardii Desml. found in Senegal, but differs from it by the 

 peculiar structure of the ambulacral rosette, which is not strictly petaloid 

 (the large fragments have the same structure), the two lines of pores of each 

 ambulacrum having a different development. In the posterior pair, the 

 anterior zone is fully developed, forming one side of the petal, while the 

 other zone is not quite half as long. It is the same with the anterior pair 

 of ambulacra, but the anterior zone is the shorter. In the odd ambula- 

 crum the left poriferous zone is the shortest. In the continuation of the 

 ambulacra from the rosette to the mouth it is always the exterior pore 

 •which is continued from each zone, and not pairs of pores, as is uniformly 

 represented in all drawings of fossil Echinolampadje. The floscelle round 

 the mouth is most distinct, but in this specimen the bourrelets were not yet 

 developed, formed as yet only by simple accumulations of small tubercles 

 closely crowded together. In still younger specimens the resemblance of the 

 opening of the actinal system to that of Clypeastroids is much greater, show- 

 ing plainly that the distinction of a suborder, founded upon the presence 

 of the bourrelets and phyllodes, as separating the Echinolampadse from the 

 Spatangoids cannot be maintained, and is simply an embryonic feature 

 which may be more or less developed. The peculiar bare space of the ac- 

 tinal part of the test, so characteristic of Pygorhynchus, and upon which 

 Desor lays so much stress, is well developed, though in older specimens of 



