•400 



PROF. P. M. DUNCAN ON THE 



[June 19. 



Notes. 



Merista variabilis, Har. (Stett. ent. Zeit. 1880), is identical with 

 Haplosonyx trifasciatus, Hope ; the type contained in the British 

 Museum agrees with v. Harold's description, tliat of Hope's being 

 unrecognizable. 



Merista rufipennis, Har., is synonymous with Leptarthra dohrni, 

 Baly, the latter author having omitted to mention in his description 

 the red colour of the elytra. 



Nerissus griseo-scutellatus, Karsch (Berlin, ent. Zeitsch. 1882, 

 December), is without doubt identical with Cheiridea subruyosa, 

 Jacoby (P. Z. S. 1882, p. 5.5). 



EXPLANATION OF PLATE XLV. 



Fig. 1. Oides apicalis, p. 399. 



2. biplagiata, p. 401. 



3. dark a, p. 4(Jl. 



■ affinis, p. 400. 



5. Mesodonta (ransverso-fasciata, 



p. 403. 



6. Packytoina gihbosa, p. 403. 



Fig. 7. Megalognafha criiciaia, p. 401. 



8. ■ unifasciata, p. 402. 



9. bipunctata, p. 402. 



10. Merista oherthiiri, p. 404. 



Phi/sonychis nigricollis, p. 404. 

 Systcna discoidalis, p. 405. 



11. 

 12. 



3. On the Madreporarian Genus Phymastrcea of Milne- 

 Edwards and Jules Haime, with a Description of a new 

 Species. By Prof. P. Martin Duncan^ F.R.S. (Com- 

 municated by Dr. Sclater^ F.R.S.) 



[Eeceived May 29, 1883.] 



CoNTTiNTS. — I. Introduction. II. The Generic Diagnoses of Phymastreea given 

 in 1848 and 1857. III. The emended Diagnosis of the Genus. IV. Descrip- 

 tion of the Species hitherto known. V. Description of a new Species. 

 VI. Kemarks on the Structures of Phymastraa irregularis, Dune. VII. The 

 Affinities of the Genus with others of the Recent Ooral-fauna. VIII. The 

 Affinities with Extinct Genera. 



I. Introduction. 



^ The species of the genus Phymastrcea are rare ; hitherto only two 

 have been described, and a third is now brought forward for the 

 first time. The genus belongs to the subfamily xVstrseaceae of the 

 family Astraeidse, and all the species are recent forms. Their struc- 

 tures are very remarkable, and recall in some points those of fossil 

 forms. 



" In fact the genus, which is remarkably well defined, is exceptional 

 amongst the recent Astraeidae, has a very old-fashioned appearance, 

 and would not have been out of place in an early Secondary coral- 

 fauna. 



The species were studied in the first instance by MM. Milne- 

 Edwards and Jules Haime, and they included them in the genus 

 Phymastrcea, which was estabhshed for the purpose in 1848'. Sub- 



' Coniptes Eendus de I'Acad^mie des Sciences, t. xxvii. p. 494. 



