当我在开发模式下运行rails服务器时，收到以下错误消息：
Sprockets::FileNotFound at /
couldn't find file 'selectize' (in /XXX/app/assets/stylesheets/application.scss:3)
我不明白这个问题因为我安装了宝石：选择轨道（0.12.4）
在 application.scss 中，我有
> /*
> *= require jquery.ui.autocomplete
> *= require selectize
> *= require selectize.default
> *= require_self
> */
#rails -v
Rails 4.1.1
#gem list
*** LOCAL GEMS ***
actionmailer (4.1.1)
actionpack (4.1.1)
actionview (4.1.1)
activemodel (4.1.1)
activerecord (4.1.1)
activesupport (4.1.1)
addressable (2.3.6)
airbrake (4.1.0)
ancestry (2.1.0)
arel (5.0.1.20140414130214)
autoprefixer-rails (3.1.1.20141001)
awesome_print (1.2.0)
backup (3.4.0)
bcrypt (3.1.7)
better_errors (2.0.0)
bigdecimal (1.2.4)
binding_of_caller (0.7.2)
bourbon (3.2.3)
brakeman (2.6.2)
buftok (0.2.0)
builder (3.2.2)
bundler (1.14.3)
capistrano (2.15.5)
celluloid (0.16.0)
choice (0.1.6)
chronic (0.10.2)
ckeditor (4.1.0)
clamp (0.6.3)
coderay (1.1.0)
coffee-rails (4.0.1)
coffee-script (2.3.0)
coffee-script-source (1.8.0)
connection_pool (2.0.0)
debug_inspector (0.0.2)
devise (3.4.0)
devise-i18n (0.11.2)
docile (1.1.5)
dotenv (0.11.1)
dotenv-deployment (0.0.2)
dragonfly (1.0.7)
elasticsearch (1.0.5)
elasticsearch-api (1.0.5)
elasticsearch-model (0.1.6)
elasticsearch-rails (0.1.6)
elasticsearch-transport (1.0.5)
equalizer (0.0.9)
erubis (2.7.0)
excon (0.40.0)
execjs (2.2.1)
fabrication (2.11.3)
faker (1.4.3)
faraday (0.9.0)
fastercsv (1.5.5)
ffi (1.9.5)
fog (1.23.0)
fog-brightbox (0.5.1)
fog-core (1.24.0)
fog-json (1.0.0)
fog-softlayer (0.3.20)
foreman (0.75.0)
formatador (0.2.5)
foundation-rails (5.4.5.0)
guard (2.6.1)
guard-minitest (2.3.2)
haml (4.0.5)
hashie (3.3.1)
highline (1.6.21)
hike (1.2.3)
hipchat (1.3.0)
hitimes (1.2.2)
http (0.6.2)
http_parser.rb (0.6.0)
httparty (0.13.1)
i18n (0.6.11)
i18n-extra_translations (0.0.6)
inflecto (0.0.2)
io-console (0.4.2)
ipaddress (0.8.0)
jbuilder (2.2.1)
jquery-fileupload-rails (0.4.1)
jquery-rails (3.1.2)
jquery-ui-rails (4.2.1)
json (1.8.1)
jwt (1.0.0)
kaminari (0.16.1)
kgio (2.9.2)
launchy (2.4.2)
letter_opener (1.2.0)
libv8 (3.16.14.7 x86_64-darwin-14)
liquid (2.6.1)
listen (2.7.11)
lumberjack (1.0.9)
mail (2.5.4)
memoizable (0.4.2)
method_source (0.8.2)
mime-types (1.25.1)
mini_portile (0.6.0)
minitest (5.4.2, 4.7.5)
minitest-spec-rails (5.1.0)
multi_json (1.10.1)
multi_xml (0.5.5)
multipart-post (2.0.0)
naught (1.0.0)
net-scp (1.2.1)
net-sftp (2.1.2)
net-ssh (2.9.1)
net-ssh-gateway (1.2.0)
nokogiri (1.6.3.1)
oauth (0.4.7)
oauth2 (1.0.0)
omniauth (1.2.2)
omniauth-facebook (2.0.0)
omniauth-oauth (1.0.1)
omniauth-oauth2 (1.2.0)
omniauth-twitter (1.0.1)
open4 (1.3.4)
orm_adapter (0.5.0)
pg (0.17.1)
polyglot (0.3.5)
pry (0.10.1)
pry-rails (0.3.2)
psych (2.0.5)
puma (2.9.1)
rack (1.5.2)
rack-cache (1.2)
rack-protection (1.5.3)
rack-test (0.6.2)
rails (4.1.1)
rails-erd (1.1.0)
railties (4.1.1)
raindrops (0.13.0)
rake (10.3.2, 10.1.0)
rb-fsevent (0.9.4)
rb-inotify (0.9.5)
rdoc (4.1.2, 4.1.0)
redis (3.1.0)
redis-namespace (1.5.1)
ref (1.0.5)
responders (1.1.1)
rubber (2.13.1)
ruby-graphviz (1.0.9)
ruby-prof (0.15.1)
ruby2ruby (2.1.3)
ruby_parser (3.5.0)
sass (3.2.19)
sass-rails (4.0.3)
sdoc (0.4.1)
selectize-rails (0.12.4)
sexp_processor (4.4.4)
sidekiq (3.2.4)
simple_oauth (0.2.0)
simplecov (0.9.1)
simplecov-html (0.8.0)
sinatra (1.4.5)
slim (2.0.3)
slim-rails (2.1.5)
slop (3.6.0)
spring (1.1.3)
sprockets (2.11.0)
sprockets-rails (2.1.4)
sqlite3 (1.3.9)
temple (0.6.8)
terminal-table (1.4.5)
test-unit (2.1.2.0)
therubyracer (0.12.1)
thor (0.19.1)
thread_safe (0.3.4)
tilt (1.4.1)
timers (4.0.1)
treetop (1.4.15)
turbolinks (2.4.0)
twitter (5.11.0)
tzinfo (1.2.2)
uglifier (2.5.3)
unicorn (4.8.3)
warden (1.2.3)
whenever (0.9.3)
yard (0.8.7.4)