NATURAL SCIENCES OF PHILADELPHIA. 491 



striatis, postice angulatis ; vagina, longissime subrecta, arenulas agglutinante, 

 liinbo ad superam extremitatem conspicue trifariam ad quinquefariam foliato ; 

 fimbria brevi, tubulis subamplis, liberis, ssepe irregularibus ; disco convexo, 

 amplo, perforationibus amplis, tumidiusculis." Reeve. 



Hob. Red Sea. 



There is but little doubt of the identity of B. Delessertianus with this 

 species. Gray and Reeve both consider it the same. The differences in 

 B. Delessertianus are not sufficient for a separation, unless the examination 

 of a large number of specimens shall prove them to be constant. 



Penicillus. 



1. P. aquaria,* Burrow, sp. 



Serpula aquaria, Burrow, Elem. p. 166, t. 22, f. 3. 



Brechites aquarius, H. and A. Adams, Genera, ii. p. 339, 1856. 



Penicillus aquarius, H. and A. Adams, Genera, ii. p. 649, 1858. 



Gray, Zool. Proc. p. 312, 1858. 

 Aspergillum sparsum, Sowberby, Genera, No. 27, f. 3-5. 

 Penicillus sparsus. H. and A. Adams, Genera, ii. p. 649, 1858. 

 Aspergillum semifimbriatum, Chenu, 111. Conch. Asp. p. 4, t. 3, f. 5. 



Catlow, Conch. Nomenc. p. 1, 1845. , 

 Reeve, Monog. Asp. t. 2, f. 5, 1860. 

 Serpula penis? (pars'* Linnaeus, Gmelin, etc. 



Description. "P. testa valvis sublate ovatis, postice subangulatis, vagina, 

 tumidiuscula, saape distorta, inferne contracts ; fimbria suberecta, tubulis 

 sub-elongatis, dichotomis ; disco parviusculo, perforationibus simplicibus." 

 Reeve. Desc. of Semifimbriatum. 

 Eab. Red Sea. 



Burrow's description of P. aquaria is entirely unsatisfactory, and he is 

 only given credit for this species, on account of his figure, which represents it 

 well enough. 



Mr. Reeve considers P. semifimbriata doubtfully distinct. Dr. Gray regards 

 it, however, as a merely distorted form of this species. The latter is un- 

 doubtedly correct, as a comparison of the figures of the two species abundantly 

 establishes. Dr. Chenu's description is drawn up from a single specimen in 

 the cabinet of Hugh Cuming. 



2. P. dichotoma,* Chenu, sp. 



Aspergillum dichotomum, Chenu, III. Conch. Asp. p. 3, t. 2, f. 6. 



Catlow, Conch. Nomenc. p. 1, 1845. 

 Reeve, Monog. Aspergillum, t. 3, f. 9, 1860. 

 Brechites dichotomus, H. and A. Adams, ii. p. 339, 1856. 

 Aspergillum disjunctum, Deshayes, Mss. in Mus. Cuming. 

 Reeve, Monog. Asp. t. 3, f. 12, 1860. 

 Description. "P. testa, valvis oblongo-ovatis, subtrapezoideis ; vagina, 

 breviuscula, superne gradatim attenuata, saepe distorta, inferne subcontract^ ; 

 fimbria subampla, valde irregulari, tubulis tenuibus elongatis promiscue dis- 

 torts et agglomeratis, saepe dichotomis ; disco parviusculo, convexo, minute 

 perforato. ' ' Reeve. 

 Hab. Singapore. 



Dr. Gray considers this species to be a variety of P. aquaria, from which it 

 constantly differs, however, in having a much more irregular frill, with the 

 tubuli more numerous. 



I have ventured, after a comparison of figures and descriptions in Reeve's 

 Monograph, to include P. disjuncta, in the synonymy of this species. 



3. P. radix,* Deshayes, sp. 



Aspergillum radix, Deshayes, Mss. in Mus. Cuming. 



Reeve, Monog. Aspergillum, t. 3. f. 11, 1860. 



1861.] 



