Evolution of tropical forestry : Puerto Rico and beyond : an interview with Frank H. Wadsworth /

"FS-610."

Pastures of Puerto Rico and their relation to soil conservation /

"U.S. Dept. of Agriculture in cooperation with the Agricultural Experiment Station, University of Puerto Rico."

Riddle-rhymes : being LII wit-waking puzzle-poems for children with thinking-caps, invented, versified and arranged for a year of Saturdays by the riddle-rhyme maker /

Mode of access: Internet.

Roster of Troops Serving in the Division of Cuba, Comprising the Departments of Matanzas and Santa Clara; Province of Havana and Pinar del Rio; Havana; and Santiago and Puerto Principe

Mode of access: Internet.

To enable the people of Puerto Rico to form a constitution and state government : hearing before the Committee on the Territories, House of Representatives, Seventy-fourth Congress, first session, on H.R. 1394 ... May 22, June 4, 18, 1935.

Mode of access: Internet.

Economic and social conditions in Puerto Rico : hearings before a Subcommittee of the Committee on Territories and Insular Affairs, United States Senate, Seventy-seventh Congress, second session, pursuant to S. Res. 309, a resolution authorizing an investigation of economic and social conditions in Puerto Rico, Washington, D.C. December 7, 8, 9, and 17, 1942.

Dennis Chavez, chairman of subcommittee.

The office of attorney general: personnel and financing; a summary of a survey of the offices of attorneys general in the 48 States, Alaska, Guam, Hawaii, and Puerto Rico.

Mode of access: Internet.

Les amusemens de Spa, or The gallantries of the Spaw in Germany : containing the virtues of every spring, their nature and several uses, the reasons why frequented by persons of the first distinctions, besides drinking the waters, the various diversions and amusements of the place, many entertaining histories of the principal persons resorting to the Spaw : intermix'd with several others of wit, humour, gaiety, &c. /

Translator's dedication signed: Hans De Veil.

Puerto Rico status : workshop before the Committee on Energy and Natural Resources, United States Senate, One Hundred Fifth Congress, second session, to provide the committee with an overview of the political status discussion in Puerto Rico.

Shipping list no.: 98-0317-P (pt. 1), 98-0351-P (pt. 2).

Act and Resolutions of the Legislative Assembly of Puerto Rico

Mode of access: Internet.

Acts and resolutions of Puerto Rico.

Numbering starts over again with 1953.

Political status of Puerto Rico : hearings before the Committee on Energy and Natural Resources, United States Senate, One Hundred First Congress, first session, on S. 710, S. 711, and S. 712.

"San Juan, Puerto Rico, June 16, 17, and 19, 1989"--Pt. 2.

Geologic and water-supply reports and maps : Puerto Rico-Virgin Islands.

Mode of access: Internet.

Chloroplast and total genomic diversity in the endemic Costa Rican tree Lonchocarpus costaricensis (J.D. Smith) Pittier (Papilionaceae).

In Mesoamerica, tropical dry forest is a highly threatened habitat, and species endemic to this environment are under extreme pressure. The tree species, Lonchocarpus costaricensis is endemic to the dry northwest of Costa Rica and southwest Nicaragua. It is a locally important species but, as land has been cleared for agriculture, populations have experienced considerable reduction and fragmentation. To assess current levels and distribution of genetic diversity in the species, a combination of chloroplast-specific (cpDNA) and whole genome DNA markers (amplified fragment length polymorphism, AFLP) were used to fingerprint 121 individual trees in 6 populations. Two cpDNA haplotypes were identified, distributed among populations such that populations at the extremes of the distribution showed lowest diversity. A large number (487) of AFLP markers were obtained and indicated that diversity levels were highest in the two coastal populations (Cobano, Matapalo, H = 0.23, 0.28 respectively). Population differentiation was low overall, F-ST = 0.12, although Matapalo was strongly differentiated from all other populations (F-ST = 0.16-0.22), apart from Cobano (F., = 0.11). Spatial genetic structure was present in both datasets at different scales: cpDNA was structured at a range-wide distribution scale, whilst AFLP data revealed genetic neighbourhoods on a population scale. In general, the habitat degradation of recent times appears not to have yet impacted diversity levels in mature populations. However, although no data on seed or saplings were collected, it seems likely that reproductive mechanisms in the species will have been affected by land clearance. It is recommended that efforts should be made to conserve the extant genetic resource base and further research undertaken to investigate diversity levels in the progeny generation.

Regional and population-scale influences on genetic diversity partitioning within costa rican populations of the pioneer tree Vochysia ferruginea mart.

The neotropical pioneer species Vochysia ferruginea is locally important for timber and is being increasingly exploited. The sustainable utilisation of this species would benefit from an understanding of the level and partitioning of genetic diversity within remnant and secondary regrowth populations. We used data from total genome (amplified fragment length polymorphism, AFLP) and chloroplast genome markers to assay diversity levels within seven Costa Rican populations. Significant chloroplast differentiation between Atlantic and Pacific watersheds was observed, suggesting divergent historical origins for these populations. Contemporary gene flow, though extensive, is geographically constrained and a clear pattern of isolation by distance was detectable when an inter-population distance representing gene flow around the central Costa Rican mountain range was used. Overall population differentiation was low (F-ST = 0.15) and within-population diversity high, though variable (H-s=0.16-0.32), which fits with the overall pattern of population genetic structure expected for a widespread, outcrossed tropical tree. However genetic diversity was significantly lower and differentiation higher for recently colonised and disturbed populations compared to that at more established sites. Such a pattern seems indicative of a pioneer species undergoing repeated cycles of colonisation and succession.