vni, D, 4 Wharton: Some Philippine Tlialassemx 251 



into 18 distinct bundles. The body wall is rather thick in both 

 terminal regions, but becomes much thinner in the middle of the 

 body. 



As in other forms the wall is made up of a corium — consist- 

 ing of the cuticle, epidermis, and dermis — the muscular layer, 

 and the endothelium. The corium layer resembles the usual 

 forms very closely. The cuticle is very thin and transparent. 

 The epidermis consists of a layer of long cylindrical cells, the 

 inner ends of which are produced into fine tapering processes 

 such as are described by other writers. All over the surface and 

 especially in the terminal regions, the epidermis is pushed out 

 by thickenings of the dermis to form small papillse. In the 

 epidermal layer of these papilla are found groups of long club- 

 shaped cells which have a granular appearance and open on the 

 surface by common pores in the cuticle. The dermis consists 

 of a clear ground substance containing numerous long anas- 

 tomosing fibers and very few cells, which gives it a more or less 

 reticular appearance. Its thickness varies greatly- in different 

 places as it forms the main internal mass of the dermal papillae. 

 Inclosed in the dermis are found numerous large rounded bodies 

 containing granules which stain deeply with hsematoxylin. They 

 do not appear to be connected with the surface, and no explana- 

 tion of their function has occurred to me. 



On taking up the study of the dermal muscle layer it was found 

 to be so different from any other form that it seemed worthy 

 of a rather detailed description. The description and drawings 

 were nearly finished when a paper by Spengel(43) was re- 

 ceived; Spengel describes specimens of T. erythrogrammon, in 

 which the skin muscle layer is very much the same as in T. 

 griffini. Spengel has compared 7 different specimens which have 

 been described at various times as T. ei'ythrogrammon. They 

 are: 



1. The original example of the species found by Riippell in the Red Sea. 



2. A specimen described by Lampert in 1883 as T. caudex and later re- 



ferred to the species T. erythrogrammon. 



3. An example in the Vienna Royal Museum, from Bourbon, identified and 



described by von Drasche in 1881. 



4. Sluiter's specimen from the Island of Billiton, between Sumatra and 



Borneo, described in 1883. 



5. A specimen collected by Willey in the China Straits near New Guinea 



and described by Shipley in 1899. 



6. An example from the Bahamas described by C. B. Wilson in 1900 and 



a specimen from Florida in the possession of Spengel. 



7. Specimens collected by Gardiner at the Maldive Islands and identified 



by Shipley in 1902. 



