eA bMS; 18%. 
Spine agreements and contrasts. 
Top row. CariBaraE: 1, 2, Agave Karatto, the second spine showing the V-like slit in 
the spine base more open than usual (St. Kitts, Shepherd); 3, A. montserratensis, showing the 
more developed spine-tip (Montserrat, Robson); 4, A. obducta, showing the still more developed 
spine proper (Antigua, Jackson); 5, A. ventum-versa, showing the very strong but still slit- 
grooved spine (St. Vincent, Sands); 6, A. unguiculata, showing the stout shallowly grooved 
spine (St. Lucia, Moore). 
Middle row. AntinnaNan: 7, A. sobolifera, with more developed and therefore heavier 
and more grooved base than usual (Jamaica, Trelease, 10); 8, A. Underwood, the typical 
form with involutely narrowed groove (Cuba, 7; release, 3); 9, A. Underwoodii, the openly 
grooved form (Cuba, Trelease, 2); 10, A. missionum (St. Thomas, Trelease, 14); 11, A. 
portoricensis, the involutely grooved spine of the eastern form (Coamo to Aibonito, Trelease, 7); 
12, A. portoricensis, the openly grooved spine of the western form (Sabana Grande, T'release, 4). 
Bottom row. BAHAMANARB: 13, A. cacozela (New Providence, Brace). ANTILLARES: 
14, A. Brittoniana brachypus, not dissimilar to the spine of A. vivipara (Cuba, Britton, Britton, 
and Wilson, 6183); 15, A. Brittoniana with short spine end and enlarged involute base— 
broken open—recalling that of Caribaeae (Cuba, Britton and Wilson, 5533). ViviParan: 16, 
A. vivipara (Curacao, Boldingh, A3). INaGuEnsrs: 17, A. Nashii Inagua, Nash and Taylor, 
1559). SISALANAE: 18, A. sisalana (St. Croix, Trelease, 27). 
All of the figures are from herbarium material and enlarged two diameters. 
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