Systematic guide to the genera and species of Rhizocephala, with anatomical diagnoses. 



113 



Host 



CMorodius areolatus 

 Maerophthalmus sp. 

 Grapsus strigosus 

 Myra fugax 

 Liipa sp. 



Pilumnus ursulus 

 Lupa sp. 

 Cancer sp. 

 Thalamita sp. 

 [Thalamita sp.) 

 Lambrus haplonotus 



Xame of Parasite 



Locality 



S. ponium 

 S. alas 

 S. flexuosa 

 S. captiva 

 S. carinata 

 S. cartieri 

 S. bi punctata 

 S. exarcuata 

 S. margaritifera 

 [S. Mans) 

 S. cacoli a ii 



(see Heterosaecus Mans) 



Gulf of Mexico — West Indies. 



Remarks. I need not add here any anatomical remarks, since the parasite of Carcinus 

 maenas has been minutely treated by Delage, and that of Inackus scorpio forms the subject of 

 many observations in this book. 



As far as is known Sacculina infests about 50 different species of Brachyura, scattered 



all over the world and at all temperatures. It is not however known to enter the arctic 



circle. The only form coming from really deep water is the parasite of Lispognathus Thompsotii 



Norman) (1180 — 1275 meters) which was shown to me by Dr. H.J. Hansen in Kjobenhavn. 



Otherwise the parasites may infest truly littoral crabs, or else in shallow water up to 100 meters. 



Note. In the diagnosis of the genus Sacculina, the lagenae of the roots are mentioned and also the retina- 

 cula which attach the egg-tubes to the mantle. Delage 16 pp. 450 and 529) has described these organs and to his 

 description I have nothing to add. With regard to the function of the lagenae I have been unable to establish 

 their excretory nature. A root of Sacculina neglecta with a lagena is figured on Plate 2 fig. 1. 



Genus Heterosaccns. 



Diagnosis. Similar to Sacculina, save that the mesentery is confined to the surface of the 

 visceral mass immediately round the ring of attachment, and does not stretch to the 

 mantle opening. 



Mantle opening, in consequence, widely gaping. 



Parasitic on Brachyura. Solitary. 



Zool. Station zu Neapel, Fauna und Flora, Golf von Neapel. Rhizocephala. 1 5 



