COLLINS. — THE ALGAE OF JAMAICA. 241 



Spring; on sand at edge of river, Castleton, Ai^ril, 1893, No. 

 364, H. 



Hormothamnion enteroraorphoides Grunow. In shallow water, St. 

 Ann's Bay; on coral reef, Navy Island, July 25, 1897, H. P. B.-A., 

 No. 56. Near Kingston, Duerden. 



*Scytonema Arcaiigelii Born. & Flah. On moist rocks by spring, 

 Castleton, April, 1893, H. 



S. conchophilum Humphrey ms. In old conch shell, Port Antonio, 

 March, 1893, H. Kingston, June, 1897, li; Producing slight, gray, 

 pustular roughenings of outside of shell, Mastigocoleus testarum occur- 

 ring on inside of same shell. 



Filaments 5-8 fx. diam., irregularly branched, branches single or gemi- 

 nate, tips rounded, cells two thirds to two times as long as broad, 2.7- 

 4.5 /A diam., pale bluish when separate. Heterocysts globose or slightly 

 elongated, 5 /u, diam., rarely two or three together, intercalary. Sheath 

 rather thin, deep yellow, homogeneous ; when old, rough outside, hyaline 

 and thin at growing tips. J. E. Humphrey. 



*S. crispum (Ag.) Bornet. On sides of trough, Constant Spring ; in 

 basin, Kingston, April, 1893, H. P. B.-A., No. 60. 



*S. densum (A. Br.) Bornet. In turfs, moist places, Port Antonio, 

 April, 1893, H. 



*S. Hofmanni Ag. On steps of Court House, Port Antonio, April, 

 1893, H. 



*S. Javanicum (Kuetz.) Bornet. On flower-pot in garden, Castleton, 

 April, 1893, H. 



*S. ocellatum (Dillw.) Thuret. On old palm stems, Castleton, April, 

 1893, H. 



*Hapalosiphon fontinalis (Ag.) Bornet. On rock, "Wag Water," 

 Castleton, April, 1893, H. 



Mastigocoleus testarum Lagerh. In old shells, Kingston, 1897, H. 



Calothrix aeruginea (Kuetz.) Thuret. On Dasya arbuscula, Montego 

 Bay, June, 1900, P. &B. 



C. confervicola (Roth) Ag. On various algae, Port Antonio, March, 

 1893, H. 



C. Contarenii (Zan.) Born. & Flah. On wreck on beach. Port Mo- 

 rant, March, 1893, H. 



*C. fusca (Kuetz.) Born. & Flah. Among Gloeocapsa quaternata, 

 Bath, 1900, P. & B. 



*C. Juliana (Meneg.) Born. & Flah. On stones in stream, Roaring 

 River, St. Ann's Bay, March, 1893, H, 

 VOL. xxxvn. — 16 



