unable to import select libs

[dtan]

i can do this from a .styl file:

@import "bootstrap"

but when i try this:

@import "bootstrap/type"

i get this error:

500 Error: site/stylus/assets/css/typography.styl:2 1| @import "bootstrap" > 2| @import "bootstrap/patterns" 3| 4| @import file bootstrap/patterns.styl
1| @import "bootstrap"
> 2| @import "bootstrap/patterns"
3|
4| failed to locate @import file bootstrap/patterns.styl
at Evaluator.visitImport (site/node_modules/stylus/lib/visitor/evaluator.js:627:21)
at Evaluator. (site/node_modules/stylus/lib/visitor/index.js:28:39)
at Evaluator.visit (site/node_modules/stylus/lib/visitor/evaluator.js:72:18)
at Evaluator.visitRoot (site/node_modules/stylus/lib/visitor/evaluator.js:499:27)
at Evaluator. (site/node_modules/stylus/lib/visitor/index.js:28:39)
at Evaluator.visit (site/node_modules/stylus/lib/visitor/evaluator.js:72:18)
at Evaluator.evaluate (site/node_modules/stylus/lib/visitor/evaluator.js:141:15)
at Renderer.render (site/node_modules/stylus/lib/renderer.js:52:26)
at site/node_modules/stylus/lib/middleware.js:140:17
at [object Object]. (fs.js:115:5)

any clues as to why i can import the entire bootstrap lib but not just a portion of it?