PART 5 A MONOGRAPH OF THE EXISTING CRENOIDS 253 



Antedon is often very abundant, but as Professor van Beneden told him he had noticed 

 when he was working at Cette, there are times when comatulids disappear entirely, 

 reappearing again later. 



Regarding the occurrence of this comatulid in the vicinity of Marseille, Professor 

 Marion (1883) says that all the stones forming the foundations of the jetty in the 

 places protected from the sun's rays down to a depth of 6 or 7 meters are covered by a 

 veritable forest of feather stars; it is rare, indeed, that a naturalist is enabled to see 

 such a profusion of crinoids. 



In the Bassin National in November 1882, a very few were dredged almost in the 

 center on a bottom of black ill-smelling mud. They had here decreased in quantity 

 over past years, and the mud on the bottom had increased in amount and had become 

 more ill-smelling. 



In the submerged zone, in to 2 meters, they occur at the head of the gulf at 

 Pharo, Madrague, Cape Janet, Mourepiano, Point Rouge de Montredon, and Fond 

 des Calanques. These several localities, subject to the influence of invasions of fresh 

 water, have certain features in common. They are the most favorable for the growth 

 of Ulvae. At certain times various animals, more particularly certain mollusks 

 Aplysias and nudibranchs are abundant, only to disappear again later. Here feather 

 stars are found rarely among the algae. 



They occur on the broad muddy stretches in the northeastern part of the gulf. 

 On the muddy bottoms off Mejeau they are found associated with Leptometra phalan- 

 gium, represented by individuals of large size with an exceptionally strong opposing 

 spine. On the muddy sand south of the island of Maire also feather stars of very 

 large size occur in 65 to 70 meters which similarly have a very prominent opposing 

 spine. 



This is especially interesting when considered in connection with the occurrence 

 in deep water in the Irish Sea of a comparable large variety of Antedon bifda, as re- 

 marked by Forbes, Norman, and others. 



On the muddy gravel south of the island of Rion and Planier in 100 to 200 meters 

 this species gives place to Leptometra phalangium, together with which are found only 

 very small individuals appearing stunted. 



At La Ciotat, Koehler (1894) found it at very different stations and depths, from the 

 littoral patches of Zostera down to muddy bottoms off shore at depths of more than 100 

 meters. In these greater depths it is associated with Leptometra phalamjium, and the 

 two together seem to form an actual carpet on the bottom, judging from the numbers 

 of individuals brought up by the dredge. 



J. Barrois (1888) says that at Toulon it is abundant along the quays and may here 

 be taken by hand in very large numbers. He notes certain differences between spec- 

 imens from Villefranche and others from Toulon. At Villefranche the individuals are 

 all spotted, showing gray and white speckles on a red background. At Toulon they 

 are much more variable, uniform red or orange, or of the same colors mixed. The 

 Villefranche variety is a little more slender than that at Toulon, and lives at some 

 depth, with the result that it is usually collected with the dredge, while at Toulon the 

 animals are abundant along the quays and may be taken by hand. 



It is found generally among algae on quaj-s and jetties in the south of France 

 (Koehler, 1921). 



Tortonese has recorded it from many places round the Ligurian Sea. 



